Non-Specialist Psychosocial Interventions for Children and ...

Non-Specialist Psychosocial Interventions for Children and Adolescents with Intellectual Disability or Lower-Functioning Autism Spectrum Disorders: A Systematic Review Brian Reichow1,2.*, Chiara Servili3., M. Taghi Yasamy3, Corrado Barbui4, Shekhar Saxena3 1 Yale Child Study Center, New Haven, Connecticut, United States of America, 2 University of Connecticut Health Center, Farmington, Connecticut, United States of America, 3 World Health Organization, Geneva, Switzerland, 4 WHO Collaborating Centre for Research and Training in Mental Health and Service Evaluation, Section of Psychiatry, Department of Public Health and Community Medicine, University of Verona, Verona, Italy

Abstract Background: The development of effective treatments for use by non-specialists is listed among the top research priorities for improving the lives of people with mental illness worldwide. The purpose of this review is to appraise which interventions for children with intellectual disabilities or lower-functioning autism spectrum disorders delivered by nonspecialist care providers in community settings produce benefits when compared to either a no-treatment control group or treatment-as-usual comparator. Methods and Findings: We systematically searched electronic databases through 24 June 2013 to locate prospective controlled studies of psychosocial interventions delivered by non-specialist providers to children with intellectual disabilities or lower-functioning autism spectrum disorders. We screened 234 full papers, of which 34 articles describing 29 studies involving 1,305 participants were included. A majority of the studies included children exclusively with a diagnosis of lowerfunctioning autism spectrum disorders (15 of 29, 52%). Fifteen of twenty-nine studies (52%) were randomized controlled trials and just under half of all effect sizes (29 of 59, 49%) were greater than 0.50, of which 18 (62%) were statistically significant. For behavior analytic interventions, the best outcomes were shown for development and daily skills; cognitive rehabilitation, training, and support interventions were found to be most effective for improving developmental outcomes, and parent training interventions to be most effective for improving developmental, behavioral, and family outcomes. We also conducted additional subgroup analyses using harvest plots. Limitations include the studies’ potential for performance bias and that few were conducted in lower- and middle-income countries. Conclusions: The findings of this review support the delivery of psychosocial interventions by non-specialist providers to children who have intellectual disabilities or lower-functioning autism spectrum disorders. Given the scarcity of specialists in many low-resource settings, including many lower- and middle-income countries, these findings may provide guidance for scale-up efforts for improving outcomes for children with developmental disorders or lower-functioning autism spectrum disorders. Protocol Registration: PROSPERO CRD42012002641 Please see later in the article for the Editors’ Summary. Citation: Reichow B, Servili C, Yasamy MT, Barbui C, Saxena S (2013) Non-Specialist Psychosocial Interventions for Children and Adolescents with Intellectual Disability or Lower-Functioning Autism Spectrum Disorders: A Systematic Review. PLoS Med 10(12): e1001572. doi:10.1371/journal.pmed.1001572 Academic Editor: R. Srinivasa Murthy, Association for the Mentally Challenged, India Received April 17, 2013; Accepted November 1, 2013; Published December 17, 2013 Copyright: ß 2013 Reichow et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: WHO supported this review through a fund from Autism Speaks (www.autismspeaks.org). The authors alone are responsible for the views expressed in this publication and these views do not necessarily represent the decisions, policy, or views of the universities by which the authors are associated, the World Health Organization, or any of the funders. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. Abbreviations: HIC, higher-income country; DQ, developmental quotient; LMIC, lower- and middle-income country; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses. * E-mail: [email protected] . These authors contributed equally to this work.

PLOS Medicine | www.plosmedicine.org

1

December 2013 | Volume 10 | Issue 12 | e1001572

Non-Specialist Psychosocial Treatment for ID/ASD

developmental disorders conducted in LMICs identified few relevant papers, and many of the studies had significant methodological shortcomings [17–19]. Thus, formulating practice guidance based solely on the findings from studies conducted in LMICs, which would provide the results with the best ecological validity, is difficult to accomplish at this time. Hence, there is a need to conduct a review that includes psychosocial interventions conducted in HICs that might be feasibly adapted for implementation in LMICs. The purpose of this review is to provide an appraisal of which interventions for children and adolescents with intellectual disabilities or lower-functioning autism spectrum disorders delivered by non-specialist care providers in community settings produce benefits in development, daily skills, school performance, behavior, or family outcomes when compared to either a no-treatment control group or treatment-as-usual comparator.

Introduction Developmental disorder is an umbrella term covering disorders such as intellectual disability/mental retardation as well as pervasive developmental disorders including autism spectrum disorders. Developmental disorders usually have a childhood onset, impairment or delay in functions related to central nervous system maturation, and a steady course that persists into adulthood. Intellectual disability, or mental retardation, is defined as ‘‘a condition of arrested or incomplete development of the mind, which is especially characterized by impairment of skills manifested during the developmental period, which contribute to the overall level of intelligence, i.e., cognitive, language, motor, and social abilities’’ [1]. Autism spectrum disorders (also called pervasive developmental disorders), such as autism, Asperger syndrome, childhood disintegrative disorder, and atypical autism, comprise a range of conditions characterized by a varied mixture of impaired capacity for reciprocal socio-communicative interaction and a restricted, stereotyped, repetitive repertoire of interests and activities. The level of intellectual functioning for individuals with autism spectrum disorders is extremely variable, extending from profound impairment to superior nonverbal cognitive skills. It is estimated that up to 50% of individuals with an autism spectrum disorder also have an intellectual disability [2]. Neurodevelopmental disorders, including intellectual disability and autism spectrum disorders, affect children worldwide, might be a more prevalent condition in lower- and middle-income countries (LMICs) compared to higher-income countries (HICs) [3], and account for more than 0.4% of all disability-adjusted life years [4]. Although most of the children and families affected by neurodevelopmental disorders live in developing countries, nearly all research, preventative efforts, and services are directed towards individuals living in the world’s wealthiest countries [5]. International evidence has shown that 75% to 85% of individuals with mental disorders in some LMICs do not receive any treatment services [6], and the lack of services prevents children from realizing a high quality of life and increases the burden on families [4]. The World Health Organization’s Atlas: Global Resources for Persons with Intellectual Disabilities [7] provides more evidence of these disparities by showing that available resources are proportional to a country’s income. In LMICs significantly fewer resources are available to dedicate to providing mental health services, and specialized human resources to deliver interventions are often either not available or available at a much lower rate than in HICs [5,7–11]. Additional barriers to increased service provision for childhood mental disorders in LMICs include the lack of evidence on effective treatments delivered in these settings and a limited capacity for identifying children with developmental disorders [9,12]. The development of effective treatments for use by nonspecialists (e.g., mental health care providers who are not psychiatrists, psychologists, or psychiatric nurse practitioners) is listed among the top research priorities for improving the lives of people with mental illness worldwide [13]. Task shifting approaches that build the capacities of a range of care providers in community settings have been successfully adopted and can be instrumental for increasing access to care for individuals with a range of mental disorders in low-resource settings [14,15]. Evidence on the effectiveness of provision of psychosocial interventions for intellectual disabilities and autism spectrum disorders by non-specialist providers in HICs is emerging [16]. Previous systematic reviews on psychosocial interventions for intellectual disabilities and autism and other pervasive PLOS Medicine | www.plosmedicine.org

Methods Selection Criteria We included studies in our review meeting the following inclusion criteria. First, the study contained participants with neurodevelopmental disorders who, on average, had a full scale IQ,70 and were, on average, under the age of 18 y. Second, the study used a prospective controlled study design, specifically, a study design comparing a treatment to a control condition, regardless of randomization. We included non-randomized controlled studies because we thought we might have difficulty locating a large pool of randomized controlled trials from which to build recommendations, and because we wanted to locate all studies with high ecological validity (e.g., studies conducted in similar contexts and under similar conditions regardless of randomization). Third, the study involved a psychosocial intervention. For this review, psychosocial intervention was defined as a therapy, education, training, or support aimed at improving behavior, general overall development, or specific life skills without the use of psychopharmacologic agents. Fourth, an individual who was not a specialist provided the psychosocial intervention or parent education to the child or parents, respectively. Stated differently, we included only studies in which a non-specialist (e.g., teacher, aide, parent, general practitioner, nurse practitioner, or local clinician) provided the direct intervention sessions to the child or conducted the parent education sessions. For this review, we considered psychiatrists, psychiatric nurse practitioners, psychologists, speech and language pathologists, occupational therapists, and physical therapists, among others, to be specialist providers. Fifth, the study was published in English, French, or Spanish. Included and excluded studies were collected following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) [20].

Search Methods We conducted an electronic database search of African Index Medicus, AFRO Library, the Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health, Embase, Western Pacific Region Index Medicus, Literatura Latino-Americana e do Caribe em Cieˆncias da Sau´de, Medline, and PsycINFO through 24 June 2013 using the search strategies shown in Texts S1, S2, S3, S4, S5. Because some of our inclusion criteria, mainly the inclusion of non-randomized studies, have the potential to increase bias, we decided not to search gray literature, which has also been considered to potentially introduce additional bias by not providing a representative sample of studies, 2



We coded two variables related to study results and findings. First, for the effect size, we calculated the standardized mean difference between the posttreatment means of the treatment and comparison groups using Cohen’s d for each outcome category, using effect size calculators based on the formulae provided in Lipsey and Wilson [32] housed on the Campbell Collaboration website (http://www.campbellcollaboration.org/resources/effect_ size_input.php). Cohen’s d [33] is an effect size reported as standard deviations (i.e., d = 1.0 is a one-standard-deviation difference between treatment and control) that is calculated by dividing the difference in mean outcome between groups by the standard deviation of outcomes among participants. Classic guidelines [33] for interpreting the magnitude of effect for Cohen’s d suggest that an effect size ,0.20 indicates no effect, 0.20–0.50 indicates a small effect, 0.50–0.80 indicates a medium effect, and .0.80 indicates a large effect. We have chosen to combine the medium and large effects in our interpretation of the magnitude of effect to reflect that many clinically significant effects can be found in effect sizes less than 0.80 but greater than 0.50. The statistical significance of effect sizes was determined by examination of the 95% CI when available. For outcomes for which effect sizes were averaged, statistical significance is indicated only if the 95% CI for all measures indicated statistical significance. When more than one outcome was included in a single study for one of our outcome categories (e.g., two separate family measures such as parent stress and quality of life), we calculated an unweighted mean of all variables within the outcome category and provided the range of effect size estimates instead of the standard deviation and 95% confidence intervals. We chose to present our effect size estimates for studies with multiple measures within one outcome category using this method because measures of the same construct within one sample are likely to be highly correlated, which can have significant impacts on mean calculations that are used to produce more standard estimates that include standard deviations and confidence intervals [34]. When multiple treatment groups receiving similar interventions were reported in one study, we averaged the posttreatment means and standard deviations for all treatment groups and compared this to the posttreatment scores from the control group. We considered synthesizing results statistically using methods such as meta-analysis, including multiple regression techniques, but decided against such analyses given the small number of studies that were ultimately located, and our decision to include randomized and non-randomized trials. Second, in addition to the effect size, we coded and reported the results of statistical significance testing, as reported in the study article, including, when available, a description of differential effects. We coded five intervention characteristic variables. First, we determined the type of psychosocial intervention, which we categorized into three categories: (a) behavior analytic interventions, (b) cognitive rehabilitation, training, and support, or (c) parent training interventions. Second, the first author created a summary of intervention methods, which is reported as the intervention description. Included in this description, at a minimum, is an indication of whether the treatment was delivered in an individual or group format (if group, the number of participants per group is provided), the location where the treatment or training sessions were conducted, and whether the intervention contained a parent component (behavior analytic and cognitive rehabilitation only). Third, we coded a variable describing who provided the treatment to the child or the training to the parents (intervention agent, training, and supervision). Within this variable, when provided in the study report, we quantified the amount of training and supervision received by the

by containing studies of lower quality, and by having more favorable results being provided more readily [21]. All titles and abstracts were initially screened by one author in order to exclude clearly irrelevant articles, and two authors, working independently and in duplicate, screened full papers of potentially relevant articles and determined which studies met all inclusion criteria. After the database search, we examined the reference lists of ten recent reviews of psychosocial interventions for individuals with developmental disabilities [17–19,22–28] for possible studies that were not located in the database search.

Variable Definitions and Coding We coded 16 variables related to research methods, participant characteristics, treatment characteristics, and study results. All variables and effect size estimates were coded independently by two abstractors, and all discrepancies were resolved through mediation. We coded four variables related to the participants of each study. First, we coded child diagnosis by indicating whether (a) all participants had a diagnosis of a lower-functioning autism spectrum disorder, (b) all participants had intellectual disability without an autism spectrum disorder, or (c) there was a mixture of participants with diagnoses of intellectual disability with an autism spectrum disorder and participants with intellectual disability without an autism spectrum disorder. Second, we coded the sample size by recording the total number of participants in the study and the number of participants in the treatment and comparison groups. Third, we calculated the mean age of the participants and provided a standard deviation and/or range when possible. Fourth, we estimated the participant’s skill level by recording the mean (and standard deviation) of an IQ or developmental quotient (DQ) when it was provided in the study report or by calculating a DQ by dividing the mean mental age by mean chronological age and multiplying by 100. When only a range was reported, e.g., IQ,70, the range was recorded and reported instead of a mean and standard deviation. We coded five variables related to the research study design and methods. First, we coded whether the study used a randomized controlled trial or quasi-experimental research design. Second, we identified the country in which the study occurred (i.e., study location). Third, within the study location, we coded whether the study occurred in a country classified by the World Bank in July 2012 as Lower Income (gross national income ,US$1,025), Lower-Middle Income (US$1,026–US$4,035), Upper-Middle Income (US$4,036–US$12,475), or High Income (US$12,476 or more). Fourth, for outcomes, we classified the measures reported in each study into one of five categories: (a) development (e.g., standardized tests of IQ, developmental progress, or language; measures of cognitive processes), (b) daily skills (e.g., adaptive behavior), (c) school performance (e.g., reading ability, literacy skills), (d) behavior (e.g., problem behavior, symptoms of behavioral disorders such as hyperactivity and inattention), or (e) family (e.g., parental stress, parental sense of competence, parenting skills). Fifth, we evaluated risk of bias using an adaptation of the Cochrane Collaboration’s Risk of Bias Tool [29] to assess eight items: sequence generation, allocation concealment, performance bias, detection bias, attrition, selective outcome reporting, protection against contamination, and baseline imbalance. The adaptations to the Cochrane Collaboration’s Risk of Bias Tool were made to accommodate our decision to include non-randomized trials and are consistent with emerging recommendations of the Cochrane Collaboration’s Non-Randomised Studies Methods Group [30,31]. PLOS Medicine | www.plosmedicine.org

3



treatment provider or parent trainer prior to and/or during the course of each study. Fourth, we quantified the intervention density by recording, if provided, the duration of each session, the number of sessions per week, and the number of weeks of treatment. Fifth, we calculated the total hours of therapy each participant received, on average, using the intervention density data we collected.

Participant Characteristics Table 1 presents the participant characteristics of the 1,305 participants across the 29 studies included in this review. The mean age of the participants ranged from 0.4 y (about 5 mo) to 15.8 y. A majority of the studies (19 of 29, 66%) had samples with a mean age less than 6 y; nine of 29 (31%) studies had a mean age of participants older than 6 y (a mean age was not able to be obtained for one study, 3%). Across studies, a majority of the studies included children exclusively with a diagnosis of a lowerfunctioning autism spectrum disorder (15 of 29, 52%); six of 29 (21%) studies included a mixture of participants with intellectual disability or lower-functioning autism spectrum disorder, and eight of 29 studies (28%) included participants who had intellectual disability without an autism spectrum disorder. Sixteen of 29 studies (55%) had IQ or DQ estimates between 50 and 69, and five of 29 (17%) studies had participants with IQ or DQ estimates below 50 (a mean IQ or DQ could not be obtained for eight of 29 studies, 28%).

Harvest Plots To examine differential treatment effects across different variables of interest (e.g., study location, participant characteristics, treatment location, treatment/training provider, treatment density), we chose to construct graphical representations of the effect size using harvest plots [35,36]. A harvest plot is a graphical display of treatment effects plotted across multiple variables, allowing for visual analysis of differential treatment effects. We chose to use harvest plots to analyze and synthesize the evidence because we determined that meta-analytic methods were not appropriate because of the large variability in intervention techniques and outcome variables. In each harvest plot we have grouped the marks (the rectangles representing study effects) on the horizontal axis according to effect size estimates corresponding to Cohen’s guidelines [33] (no effect, effect size ,0.20; small effect, effect size = 0.20–0.49; and medium to large effect, effect size .0.50). The marks are grouped on the vertical axis by the type of psychosocial intervention (behavior analytic interventions; cognitive rehabilitation, training, and support; and parent training) that was used in each study. The heights of the marks represent the research methodology used in the study, with the taller marks indicating studies using randomized controlled trials and the shorter marks indicating studies using quasi-experimental designs. Statistical significance (determined by examination of the 95% CI when available) is indicated in the harvest plots for each study outcome by an asterisk above the mark. The marks are also color-coded by outcome category (black = development, gray = daily skills, white = school performance, vertical stripes = behavior, and horizontal stripes = family). We have indicated participant diagnostic categories for each study using black bars that are placed above the marks. Participant diagnostic characteristics (i.e., all participants had intellectual disability, all participants had lower-functioning autism spectrum disorder, or the study contained a mixture of participants with both intellectual disability and lower-functioning autism spectrum disorder) are indicated above each mark. Finally, all harvests plots contain multiple panels, which are labeled above each plot (e.g., comparison of results between outcomes, comparison between levels of cognitive impairment).

Intervention Characteristics Tables 2–4 provide information on the intervention characteristics across types of psychosocial intervention for studies using behavior analytic techniques; cognitive rehabilitation, training, and support; and parent training interventions, respectively. The treatment agents (e.g., therapists) typically delivered interventions with multiple hours of treatment per week (range 1 to 40 h per week). Treatment duration for the behavior analytic studies and cognitive rehabilitation, training, and support studies was often long, lasting, in many cases, over 100 wk (range 3 to 156 wk); the duration of parent training interventions was typically much shorter, with most lasting between 8 and 12 wk. As seen in the intervention description, a variety of methods and curricula were used across studies. Given that the behavior analytic and cognitive rehabilitation, training, and support studies had higher weekly treatment densities and longer treatment durations, it is not surprising that the number of total contact hours was higher in these studies (range 18 to 6,240 h) than in studies of parent training interventions (range 5 to 52 h). Table 5 provides an overview of the intervention agents, with training and supervision requirements, across all studies. There were multiple types of nonspecialist providers including teachers (n = 12), aides (n = 10), and community therapists/clinicians (n = 6). A majority of the studies reported that training and/or ongoing supervision of the nonspecialist providers occurred, albeit often with little specificity. When reported, the frequency and duration of training and supervision varied highly across studies from ‘‘ongoing on-the-job training’’ to over 40 h of initial training before beginning to deliver treatment.

Research Characteristics

Results

Tables 6–8 show the research characteristics for studies using behavior analytic techniques; cognitive rehabilitation, training, and support; and parent training interventions, respectively. Just over half of the studies (15 of 29, 52%) used randomized controlled trial designs; prospective controlled study designs were used in 14 studies. Western Europe (12 of 29, 41%) and North America (United States and Canada; eight of 29, 28%) were the most common locations of the research studies included in this review. Of the remaining nine studies, six (21%) were conducted in Asia, two (7%) in Australia, and one (3%) in Africa. Six studies (21%) were conducted in countries classified by the World Bank as LMICs; each of these studies was conducted in a country classified as Lower-Middle Income. A majority of the studies conducted in LMICs examined parent training interventions. There was great

Search Results We located 20,806 records; 17,501 records remained after deduplication. Two hundred thirty-four articles remained after the first author screened the titles and abstracts. The first and second authors examined the 234 full papers independently, and in duplicate, for inclusion in this review. Our database search located 34 articles describing 29 studies that met all inclusion criteria. The primary reasons for exclusion are provided in Text S6 and are shown in the PRISMA flow diagram of Figure 1. No additional studies were located in the hand search of previous reviews. We have used study as the unit of analysis for all results to ensure that studies reported in multiple articles are not weighted more heavily than those presented in one article. PLOS Medicine | www.plosmedicine.org

4



Figure 1. Study inclusion decision tree (using PRISMA flow diagram [20]). doi:10.1371/journal.pmed.1001572.g001


5



Table 1. Included studies and participant characteristics.

First Author and Year of Publication of Original Study [Reference]

Child Diagnosis

n (T, C)a

Age (Years) (SD; Range)

Mean (SD) Skill Level

Behavior analytic techniques Kaale 2012 [66]

ASD

51 (34, 27)

4.1 (0.7; 2.0–5.0)

DQ: 56.6 (19.5)

Dawson 2010 [61,71]

ASD

45 (24, 21)

2.0 (0.3; 1.5–2.5)

IQ: 60.2 (8.9)

Smith 2000 [70]

ASD

28 (15, 13)

2.9 (0.5; 1.5–3.5)

IQ: 50.6 (12.6)

Jocelyn 1998 [65]

ASD

35 (16, 19)

3.6 (0.8; 2.0–6.0)

IQ: 62.8 (27.5)

Eikeseth 2012 [63]

ASD

59 (35,24)

4.1 (2.1; 2.0–7.3)

DQ: 48.2 (n/a)

Peters-Scheffer 2010 [67]

ASD

34 (12, 22)

4.5 (0.7; 3.0–6.0)

DQ: 46.4 (13.2)

Eikeseth 2007 [62,72]

ASD

25 (13, 12)

5.5 (0.9; 4.0–7.0)

IQ: 63.6 (13.2)

Reed 2007 [68]

ASD

32 (12, 20)

3.5 (n/a; 2.7–3.9)

IQ: 52.9 (6.3)

Remington 2007 [69,73]

ASD

44 (23, 21)

3.1 (0.4; 2.5–3.5)

IQ: 61.9 (16.5)

Cohen 2006 [60]

ASD

42 (21, 21)

2.7 (0.4; 1.5–3.5)

IQ: 60.5 (15.6)

Howard 2005 [64]

ASD

45 (29, 16)

2.9 (0.5; 0–4.0)

IQ: 59.2 (16.6)

IQ: 42.5 (13.0)

Cognitive rehabilitation, training, and support Browder 2012 [76,85]

ASD, ID

93 (47, 46)

n/a (n/a; 8.0–11.0)

Burgoyne 2012 [77]

ID

57 (29, 28)

6.6 (1.3; 5.0–10.0)

IQ: ,70b (n/a)

Allor 2010 [75,84]

ASD, ID

59 (34, 25)

7.9 (1.5; n/a)

IQ: range 40–69

Elwan 2010 [78]c

ID

40 (10, 10, 10, 10)d

4.9 (0.6; n/a)

IQ: 60 (estimated)

Panerai 2009 [81]

ASD

23 (13, 10)

8.9 (2.1; n/a)

DQ: 20.9 (n/a)

Goetz 2008 [79]

ID

15 (8, 7)

10.2 (n/a; 8.0–12.0)

IQ: ,70b (n/a)

Perez 2008 [82]

ID

113 (63, 50)

n/a (n/a; 11–16)

IQ: 52.7 (10.5)

Tsang 2007 [83]c

ASD

34 (18, 16)

4.1 (0.6; 3.0–5.9)

IQ: 67.1 (14.6)

Jespen 2002 [80]

ASD, ID

46 (23, 23)

15.8 (n/a; 14.0–16.0)

IQ: 57 (1.1)

Wong 2010 [94]c

ASD

17 (9, 8)

2.2 (0.5; 1.4–3.0)

DQ: 67.4 (n/a)

Shin 2009 [91]c

ID

20 (6, 14)

4.5 (1.0; 3.0–6.0)

IQ: ,70b (n/a)

Parent training interventions

Plant 2007 [88]

ASD, ID

74 (26, 24, 24)

4.6 (1.1; 0–6)

IQ: ,70b (n/a)

Del Giudice 2006 [86]

ID

32 (21,11)

0.4 (0.2; n/a)

DQ: 54.3 (22.6)

Roberts 2006 [89]

ASD, ID

32 (17, 15)

4.3 (1.0; n/a)

IQ: 62.5 (16.6)

Russell 1999 [90]c

ID

52 (26, 26)

6.4 (2.7; 0–13.0)

IQ: ,70b (n/a)

Varma 1992 [93]

c

e

ID

80 (40, 40)

7.3 (2.3; 3.0–10.0)

IQ: 49.9 (10.6)

McConachie 2005 [87]

ASD, ID

51 (26, 25)

3.1 (0.6; 2.0–4.0)

IQ: ,70b (n/a)

Shu 2005 [92]

ASD

27 (8, 19)

Not reported

Not reported

DQ calculated as mean mental age/mean chronological age 6 100. a Total number of children in study (n) and the number of children in the treatment (T) and control (C) groups. b IQ estimate based on our interpretation of participant characteristics. c LMIC status according to the World Bank. d This study contained three treatment groups and one control group (n = 10). e This study contained two treatment groups and one control group (n = 24). ASD, autism spectrum disorder; ID, intellectual disability; n/a, not available; SD, standard deviation. doi:10.1371/journal.pmed.1001572.t001

outcomes were measured using developmental assessments [37– 39], standardized IQ tests [38,40–47], and standardized language tests [48–58]), while daily skills were mostly measured using a single measure (i.e., Vineland Adaptive Behavior Scale [59]). Additional details on the measures and assessments used in each study by outcome type can be found in Table S1. Two independent raters assessed eight potential biases in all studies, which are shown as an average across all studies in Figure 2 and for each study by indicator in Figure S1. As seen in Figures 2 and S1, performance bias was a risk in all studies included in the review. This is likely due to the nature of psychosocial interventions, which involve interaction between providers and

variability with respect to the number and types of outcomes measured across studies. Within our outcome categories, some studies measured only one outcome category, while other studies measured up to four outcome categories (no study measured all five outcome categories). Developmental and daily skill outcomes were measured more frequently in psychosocial interventions utilizing behavior analytic techniques and cognitive rehabilitation, while family outcomes were measured more frequently in parent training programs. There was also great variability with respect to the measurement instruments used within each outcome category. For instance, developmental outcomes were measured using a number of different standardized assessments (e.g., developmental


6



Table 2. Intervention description, intervention density, and total hours of intervention for behavior analytic intervention studies.


Child Diagnosis

Intervention Description

Intervention Density

Kaale 2012 [66]

ASD

Joint-attention training based on Kasari et al. [102] combining developmental and behavioral treatment approaches delivered by a teacher in a school setting during 1:1 instruction

Ten 20-min sessions per week for 8 wk

Dawson 2010 [61,71]

ASD

A developmentally sequenced behavioral treatment based on the Early Start Denver Model [103] delivered in a 1:1 instructional format by a therapist in the child’s home with ongoing parent involvement

Ten 2-h sessions per week; 1,870 h M = 15.2 (SD = 1.4) h per week for 123 (SD = 14.6) wk

Smith 2000 [70]

ASD

Intensive applied behavior analysis based on Lovaas [104] model providing intensive behavioral treatment delivered mostly in a 1:1 instructional format by instructional aides in the child’s home, with ongoing parent involvement

18–31 h per week (M = 24.5, SD = 3.7) for M = 143.8 (SD = 47.3) wk

3,523 h

Jocelyn 1998 [65]

ASD

Caregiver-based intervention program delivered in 1:1 format in child care settings by providers who received training on behavioral principles in behavior management with an additional parent component

M = 21.4 h per week for 12 wk

257 h

Eikeseth 2012 [63]

ASD

Applied behavior analysis based on Lovaas [104,105] manuals providing intensive behavioral treatment delivered mostly in a 1:1 instructional format by instructional aides in a school setting with ongoing parent involvement

15–37 h per week (M = 23.0) for 52 wk

1,196 h


ASD

Low-intensity behavior analytic intervention delivered in a school setting by an instructional aide in a 1:1 instructional format including additional parent training

5–10 h per week (M = 6.3) for 34 wk

214 h

Eikeseth 2007 [62,72]

ASD

Applied behavior analysis based on Lovaas [104,105] manuals providing intensive behavioral treatment delivered mostly in a 1:1 instructional format by instructional aides in the child’s home with ongoing parent involvement

18–28 h per week for 135 wk

2,430–3,780 h

Reed 2007 [68]

ASD

Intensive behavior analytic intervention [104,106,107] provided mostly in a 1:1 instructional format by instructional aides in the child’s home

20–40 h per week (M = 30.4) for 43 wk

1,307 h


ASD

Intensive behavior analytic intervention based on Green et al. [108] manual providing intensive behavioral treatment delivered mostly in a 1:1 instructional format by instructional aides in the child’s home with ongoing parent involvement

18–30 h per week; M = 25.6 (SD = 4.8) h of treatment per week for 104 wk

2,662 h

Cohen 2006 [60]

ASD

Applied behavior analysis based on Lovaas [105] manual providing intensive behavioral treatment delivered mostly in a 1:1 instructional format by instructional aides in the child’s home with ongoing parent involvement


5,460–6,240 h

Howard 2005 [64]

ASD

Applied behavior analysis based on treatment programs described in the manuals of Maurice et al. [109,110] providing intensive behavioral treatment delivered mostly in a 1:1 instructional format by instructional aides in the child’s home with ongoing parent involvement


1,525–2,440 h

Total Hours of Treatment 27 h

No behavior analytic intervention studies were conducted in LMICs (LMIC status per World Bank). ASD, autism spectrum disorder; ID, intellectual disability; M, mean; SD, standard deviation. doi:10.1371/journal.pmed.1001572.t002

Intervention Characteristics and Treatment Effects

either the children with disabilities or the parents of the children. Given that many of the studies had low risk of detection bias, it is unclear what effect the high risk of performance bias might have had on the results. There was moderate risk of selection bias, most likely due to our inclusion of non-randomized studies. There was also moderate risk of contamination bias, which was due to the high risk of contamination in many of the behavior analytic studies that used eclectic comparison groups that potentially included elements of the behavioral treatments.


Across studies there was a large range of effect size estimates, from a low of 21.89 to a high of 2.51. A large majority of the effect size estimates were positive (45 of 59, 76%), with just under half (29 of 59, 49%) being greater than 0.50, the threshold we took to suggest clinical significance. Eighteen of these 29 effect size estimates greater than 0.50 were statistically significant across intervention types. As shown in Figure 3, for the behavior analytic interventions, the best outcomes shown were for development and

7



Table 3. Intervention description, intervention density, and total hours of intervention for cognitive rehabilitation, training, and support intervention studies.


Child Diagnosis



Browder 2012 [76,85]

ASD, ID

Early Literacy Skills Builder [111] curriculum delivered in small groups (size 2–4) delivered in schools using behavioral strategies including response-prompting techniques

Five 20-min sessions per week for 30 wk

50 h

Burgoyne 2012 [77]

ID

Multicomponent phonics-based reading program with language instruction delivered in a 1:1 instructional format


133 h

Allor 2010 [75,84]

ASD, ID

300 direct instruction small group instructional sessions delivered in the school targeting reading based on Early Interventions in Reading [112]

Five 40–50-min sessions per week for 60 wk

200–250 h

Elwan 2010 [78]a

ID

T1: integration of child with disability with small group of peers without disabilities in school; T2: cognitive training during 1:1 instruction in school; T3: T1 and T2

T1: 2 h per day 3 d per week for 3 wk; T2: eight 1-h sessions for 3 wk

T1: 18 h; T2: 24 h

Panerai 2009 [81]

ASD

Full-time schooling incorporating principles of TEACCH program [113] delivered in schools including daily 1:1 instruction and an additional parent component (natural setting TEACCH group used for analyses, not residential)

Treatment provided during school day for 156 wk

5,460 h

Goetz 2008 [79]

ID

Phonological awareness intervention based on Jolly Phonics [114] and reading intervention [115] with additional speech-based component delivered during 1:1 instruction in school


27 h

Perez 2008 [82]

ID

Special needs curriculum based on Gardner’s multiple intelligences [116] and Anderson and Krathwohl’s revision of Bloom’s taxonomy [117], which provided students with individualized instruction in school

Treatment (curricula) used 4 h per week for one school year (about 40 wk)

160 h

Tsang 2007 [83]a

ASD

Full-time schooling incorporating principles of TEACCH program [113] delivered in school with 6–8 students with emphasis on visual structure and schedules as well as use of individualized work systems

7 h per day for 26 wk

910 h

Jespen 2002 [80]

ASD, ID

Cognitive education program involving individual, small group, and whole class lessons in school in which cognitive functions and strategies were mediated by teachers seeking to relate these functions to the student’s everyday environments and routines

Treatment (curricula) used for 1 h per week for one school year (about 40 wk)

40 h

Total Hours of Treatment

a LMIC status according to the World Bank. ASD, autism spectrum disorder; ID, intellectual disability; T1, T2, T3, treatment groups for studies with multiple treatments; TEACCH, Treatment and Education of Autistic and Related Communication Handicapped Children. doi:10.1371/journal.pmed.1001572.t003

lower-functioning autism spectrum disorders who were, on average, under the age of 6 y at the onset of treatment. As shown in Figure 3, effect size estimates for the behavior analytic psychosocial interventions were generally robust, especially for daily skills, for which seven of nine (78%) effect size estimates were greater than 0.50, with six of seven effect size estimates greater than 0.50 having statistical significance. However, only one study with a large statistically significant effect size was a randomized controlled trial [61]. Mixed results were shown for developmental and behavioral outcomes, although two randomized controlled trials [61,70] showed large effects for developmental outcomes, of which one was statistically significant. Only a few studies measured family outcomes, and no study of behavior analytic interventions examined school performance, even though three studies were conducted in a school setting [63,66,67]. The results from the comparison of mean participant age shown in Figure 6 suggests that behavior analytic techniques appear to be most effective for children under 3 y old, where four of seven effect size estimates .0.50 were found in randomized controlled trials

daily skills. For the studies of cognitive rehabilitation, training, and support, shown in Figure 4, the best outcomes were for developmental outcomes in children with intellectual disabilities between 6 and 11 y of age. For the parent training interventions, shown in Figure 5, the best outcomes were found for developmental, behavioral, and family outcomes. More detailed analyses, including subgroup analyses by type of intervention, are presented below. Psychosocial interventions delivered using behavior analytic techniques. Fourteen articles representing 11 studies

[60–73] described psychosocial interventions provided by nonspecialist providers that used treatments based on the science of applied behavior analysis [74]. Table 2 provides descriptions of the intervention techniques and intervention density for each study, and Table 6 provides descriptions of the research characteristics and outcomes for each behavior analytic study. As shown in Table 6, four of 11 studies [61,65,66,70] were randomized controlled trials, and zero studies were conducted in LMICs. As described in Table 1, these studies included 440 children with PLOS Medicine | www.plosmedicine.org

8



Table 4. Intervention description, intervention density, and total hours of intervention for parent training intervention studies.


Child Diagnosis



Wong 2010 [94]a

ASD

Clinic-based individual parent training using the Autism 1-2-3 program, which teaches parents techniques for increasing their child’s eye contact, gestures, and vocalizations

Five 0.5-h sessions per week for 2 wk

5h

Shin 2009 [91]a

ID

Individual in-home parent training based on the Portage curriculum [118] training parents to work with their children in the absence of professional resources

One 1-h session per week for 52 wk

52 h

Plant 2007 [88]

ASD, ID

T1: clinic-based individual parent training using Stepping Stones Triple P [119] model teaching parents how to promote development and manage behavioral problems; T2: T1 plus six enhanced training sessions

T1: one 1–1.5-h session per week for 10 wk; T2: one 1–1.5-h session per week for 16 wk

T1: 10–15 h; T2: 16–24 h


ID

Individual developmentally based training for parents of children with Down syndrome emphasizing 26 developmental sequences

About one session per month for 52 wk

Not specified

Roberts 2006 [89]

ASD, ID

Clinic-based individual parent training using the Stepping Stones Triple P [120] model instructing parents in how to identify causes of behavior problems and manage problem behavior while encouraging child development; included home visits

One 2-h session per week for 10 wk

20 h

Russell 1999 [90]a

ID

Clinic-based group interactive psychoeducation teaching parents about Down syndrome and intellectual disability, raising a child with disability, developmental milestones, and behavioral treatment methods

Two 1-h sessions per week for 10 wk

20 h

Varma 1992 [93]a

ID

Clinic-based individual parent training focusing on teaching parents broad information about intellectual disabilities and how to deliver behavioral modification in home settings

About one 1-h session per week for 3 mo

12 h


ASD, ID

Clinic-based parent training delivered in groups of eight based on the More Than Words [121] curriculum, which teaches parents techniques for facilitating social interaction and communication with their child; included home visits

One 2.5-h session per week for 8 wk

24 h

Shu 2005 [92]

ASD

Clinic-based group (size eight) support for mothers of children with intellectual disability focused on teaching the mothers how to handle stressors commonly associated with raising a child with a disability

One 90-min session per week for 10 wk

15 h

Total Hours of Treatment

a LMIC status according to the World Bank. ASD, autism spectrum disorder; ID, intellectual disability; T1, T2, treatment groups for studies with multiple treatments. doi:10.1371/journal.pmed.1001572.t004

[61,70]. Five of seven (71%) effect size estimates for children under 3 y old were statistically significant, including two of four (50%) estimates from randomized controlled trials. Strong effects were also shown for children who were between 3 and 6 y old, although effect size estimates for three outcomes were ,0.20. As shown in Figure 7, no behavior analytic studies included participants at pretreatment who were, on average, older than 6 y old. As shown in Figure 8, behavior analytic interventions seem quite effective for individuals with moderate to severe intellectual impairment; all effect size estimates from Eikeseth et al. [63] and Peters-Scheffer et al. [67] were greater than 0.50, with three of four (75%) estimates having statistical significance. For individuals with milder intellectual impairment, the behavior analytic interventions seemed effective at improving daily skills and developmental outcomes, which had, respectively, four and two effect size estimates greater than 0.50 that were statistically significant. PLOS Medicine | www.plosmedicine.org

Figure 9 shows that behavior analytic interventions provided in schools had mixed effects; four of eight (50%) effect size estimates showed strong effects (three of four were statistically significant), and four of eight (50%) effect size estimates showed weak or no effects. For interventions conducted in a home setting, 11 of 20 (55%) effect size estimates were greater than 0.50, with six of the 11 (55%) estimates having statistical significance. In home and school settings, daily skills outcomes showed the most promising effects. Differential effects for other outcomes across settings showed inconclusive results (e.g., behavioral and family outcomes). As shown in Table 2, the majority of behavior analytic studies involved intensive amounts of treatment; nine of 11 (82%) studies provided children with more than 10 h of treatment per week, with durations frequently lasting at least 52 wk. Many of these interventions also had significant amounts of treatment provider supervision, with some studies employing complex multilevel supervision arrangements with intensive training requirements 9



Table 5. Intervention agent and training and supervision for included studies.


Child Diagnosis

Agent

Training and Supervision

Behavior analytic techniques Kaale 2012 [66]

ASD

Teacher

1 d training and weekly supervision

Dawson 2010 [61,71]

ASD

Therapist

2 mo training and weekly supervision

Smith 2000 [70]

ASD

Aide

Ongoing training and supervision (type and density not specified)

Eikeseth 2012 [63]

ASD

Aide

Ongoing training through 2 h per week supervision


ASD

Aide

Workshop training (density not specified) and monthly supervision

Eikeseth 2007 [62,72]

ASD

Aide

Ongoing training through 10 h per week supervision

Reed 2007 [68]

ASD

Aide



ASD

Aide

Ongoing training (type and density not specified) and monthly supervision

Cohen 2006 [60]

ASD

Aide


Howard 2005 [64]

ASD

Aide


Jocelyn 1998 [65]

ASD

Teacher

15 h training (five 3-h workshops) and 3 h per week supervision

Cognitive rehabilitation, training, and support Browder 2012 [76,85]

ASD, ID

Teacher

2 d training and ongoing supervision

Burgoyne 2012 [77]

ID

Teacher

5 d training and quarterly supervision

Allor 2010 [75,84]

ASD, ID

Teacher

9 d training and monthly supervision

a

ID

Teacher

Not specified

Panerai 2009 [81]

ASD

Aide

Not specified

Goetz 2008 [79]

ID

Aide

2 d training and supervision every other month

Perez 2008 [82]

ID

Teacher

Teacher was trained, but type and density of training not specified

Tsang 2007 [83]a

ASD

Teacher


Jespen 2002 [80]

ASD, ID

Teacher


Wong 2010 [94]a

ASD

Therapist

Training provided, but type and density not specified

Shin 2009 [91]a

ID

Teacher

3 mo of weekly training and supervision every 3 wk

Plant 2007 [88]

ASD, ID

Practitioner



ID

Local therapists


Roberts 2006 [89]

ASD, ID

Teacher, SLP, OT, or psychologist

40 h training and ongoing supervision

Russell 1999 [90]a

ID

Special educator or psychologist

Not specified

Elwan 2010 [78]

Parent training interventions

Varma 1992 [93]a

ID

Local clinician

Not specified


ASD, ID

Local clinicians

Training provided by Hanen Centre (density not specified) with one supervision visit

Shu 2005 [92]

ASD

Nurse (training and supervision not specified)

Not specified

a LMIC status according to the World Bank. ASD, autism spectrum disorder; ID, intellectual disability; OT, occupational therapist; SLP, speech and language pathologist. doi:10.1371/journal.pmed.1001572.t005

.10 h of treatment per week). However, the majority of these estimates came from studies that did not use random assignment to groups, and only seven of 12 (58%) effects were statistically significant. Additionally, there were no comparisons of intervention

[64,70]. That the majority of behavior analytic studies involved intense amounts of treatment is also depicted in Figure 10, in which a majority of the effect size estimates in the plot are contained in the second panel (the panel showing studies with


10



Table 6. Research design, results, and effect sizes for behavior analytic intervention studies.


Child Diagnosis

Design

Results by Outcome

Effect Size by Outcome

Kaale 2012 [66]

ASD

RCT

Intervention group had significantly higher levels of joint attention and joint engagement [57] (development)

Range d = 20.31 to 0.57 (M = 0.16)

Dawson 2010 [61,71]

ASD

RCT

Intervention group had significantly higher scores at follow-up for the developmental outcome [37] (a) and daily skills [59] (b), but no difference in restricted and repetitive behavior [122] (c)

(a) d = 0.60 (95% CI 0.00–1.20), (b) d = 0.73 (95% CI 0.13–1.34), (c) d = 0.36 (95% CI 20.23 to 0.95)

Smith 2000 [70]

ASD

RCT

Intervention group had significantly higher IQ [41,42,123] (development) (a) and lower levels of parent stress [124] (family) (d), but no differences were shown for language [48] (development) (a), daily skills [59] (b), or problem behavior [125] (c)

(a) range d = 0.37 to 0.76 (M = 0.54), (b) d = 0.11 (95% CI 20.64 to 0.85), (c) range d = 0.14 to 0.23 (M = 0.19), (d) d = 0.98 (95% CI 20.20 to 1.77)

Jocelyn 1998 [65]

ASD

RCT

Intervention group had significantly better language subscale scores (development) (a), but no differences in other developmental [126] (a), behavior [127] (b), or family outcomes [128,129] (c)

(a) range d = 20.18 to 0.67 (M = 0.14), (b) range d = 0.20 to 0.41 (M = 0.31), (c) range d = 20.52 to 0.30 (M = 20.10)

Eikeseth 2012 [63]

ASD

QE

Intervention group had significantly higher scores in daily skills [59]

d = 0.93 (95% CI 0.38–1.47)


ASD

QE

Intervention group had significantly higher IQ [38] (development) (a) and daily skills [59] (b), but no statistically significant difference in behavior [125] (c)

(a) d = 0.75 (95% CI 0.03–1.48), (b) d = 1.09 (95% CI 0.34–1.84), (c) d = 0.61 (95% CI 20.11 to 1.33)

Eikeseth 2007 [62,72]

ASD

QE

Intervention group had significantly higher IQ [38,45,130] (development) (a) and daily skills [59] (b) at follow-up at age 8 y, and lower levels of aggression and socially inappropriate behavior [125] (behavior) (c)

(a) d = 0.56 (95% CI 20.25 to 1.38), (b) d = 1.20 (95% CI 0.33–2.07), (c) range d = 0.11 to 1.41 (M = 0.48)

Reed 2007 [68]

ASD

QE

Intervention group had a significantly better developmental outcome [131] (a) and daily skills [59] (b)

(a) range d = 0.34 to 0.47 (M = 0.41), (b) d = 0.54 (95% CI 20.19 to 1.27)


ASD

QE

Intervention group had significantly higher IQ [38,41] (development) (a), improved outcomes on daily skills and motor subscales [59] (b), and fewer problem behaviors [132,133] (c), but no differences for joint attention [48,57] (a), composite daily skills [59] (b), or family outcomes [134–136] (d)

(a) range d = 0.05 to 0.49 (M = 0.28), (b) d = 0.33 (95% CI 20.27 to 0.92), (c) d = 0.58 (95% CI: 20.07 to 1.23), (d) range d = 20.28 to 0.23 (M = 20.02)

Cohen 2006 [60]

ASD

QE

Intervention group had significantly higher scores for IQ and receptive language [38,42] (development) (a) and daily skills [59] (b)

(a) range d = 0.41 to 0.61 (M = 0.48), (b) d = 0.69 (95% CI 0.07–1.31)

Howard 2005 [64]

ASD

QE

Intervention group had significantly higher scores for IQ [38,40–47] and language [48–56] (development) (a) and daily skills [40,59,137,138] (b)

(a) range d = 0.99 to 1.36 (M = 1.11), (b) d = 1.01 (95% CI 0.35–1.68)

No behavior analytic intervention studies were conducted in LMICs (LMIC status per World Bank). ASD, autism spectrum disorder; d, Cohen’s d; M, mean; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.t006

intensity in any of the studies included in this review; thus, it is not possible to conclude a true relation between treatment density and outcome. Overall, the effects for the high-intensity interventions were somewhat mixed, whereas the outcomes for the interventions with fewer than 10 h of treatment per week showed some promising outcomes. Jocelyn et al. [65] found significant improvement in standardized language scores, but not other developmental outcomes, using an intervention with moderate weekly density (mean = 21 h) with a shorter duration than most behavior analytic treatments (12 wk). Two studies examined interventions with densities lower than 10 h per week, with Kaale et al. [66] finding mixed results (significant increases in some but not all aspects of joint attention), and Peters-Scheffer et al. [67] finding strong effects for IQ, daily skills, and behavior, with effect sizes for all exceeding d = 0.60.


Psychosocial interventions delivered using cognitive rehabilitation, training, and support. We located 11 articles

representing nine studies [75–85] involving 480 children with intellectual disabilities or lower-functioning autism spectrum disorders in which non-specialist providers delivered cognitive rehabilitation, training, and support interventions. Table 3 provides descriptions of the intervention techniques and intervention density for each study, and Table 7 provides descriptions of the research characteristics and outcomes for each cognitive rehabilitation, training, and support study. Four of nine (44%) studies [75–78] were randomized controlled trials, and two studies were conducted in LMICs [78,83]. All studies occurred in school settings, with some focusing on specific curricular areas [75–77] and others incorporating curricular approaches to whole day instruction [81,82]. As shown in Table 5, both teachers and aides,

11



Table 7. Research design, results, and effect sizes for cognitive rehabilitation, training, and support intervention studies.


Child Diagnosis

Design

Results by Outcome


Browder 2012 [76,85]

ASD, ID

RCT

Intervention group had significantly better literacy scores [139] (school performance) (b), with smaller effects for the language outcome [49,140] (development) (a)

(a) d = 0.30 (95% CI 20.11 to 0.71, (b) range d = 0.44 to 0.50 (M = 0.47)

Burgoyne 2012 [77]

ID

RCT

Intervention group showed superior performance on early reading skills [141,142] (school performance) (b), but no difference in standardized language tests [55,56] (development) (a)

(a) range d = 0.04 to 0.16 (M = 0.10), (b) range 20.25 to 0.71 (M = 0.25)

Allor 2010 [75,84]

ASD, ID

RCT

Intervention group had significantly higher scores for blending nonwords, segmenting words, and word attack (school performance) (b), but no significant differences for development [49,140] (a) and other school performance [143–145] (b)

(a) range d = 0.32 to 0.45 (M = 0.38), (b) range d = 0.23 to 0.65 (M = 0.42)

Elwan 2010 [78]a

ID

RCT

T2 group had significantly better developmental outcomes [146,147] than T1, T3, and control groups

Range d = 1.61 to 3.51 (M = 2.51)

Panerai 2009 [81]

ASD

QE

Natural setting intervention group had significantly higher developmental [44] (a) and daily skills [59] (b) outcomes

(a) d = 1.22 (95% CI 0.33–2.12), (b) d = 0.87 (95% CI 0.00–1.73)

Goetz 2008 [79]

ID

QE

Intervention group had significantly higher scores on letter knowledge and early word recognition but not for word and nonword reading [115,131,148,149] (school performance)

Range d = 0.29 to 1.57 (M = 0.93)

Perez 2008 [82]

ID

QE

Intervention group had significantly higher scores on mathematics, language arts, and social science examinations (school performance) (b), but minimal differences were found for IQ [41] (development) (a)

(a) d = 0.37 (95% CI 20.02 to 0.73), (b) range d = 1.39 to 1.61 (M = 1.47)

Tsang 2007 [83]a

ASD

QE

Both groups made gains, but intervention group had significantly lower scores on development [42,150] (a) and daily skills [151] (b)

(a) range d = 21.27 to 20.98 (M = 21.13), (b) d = 21.89 (95% CI 22.70 to 1.08)

Jespen 2002 [80]

ASD, ID

QE

Intervention group showed modest gains between pre- and post-intervention for developmental outcomes [152] (a), daily skills [153] (b), and school performance [154] (c); differences between groups after intervention were not statistically significant

(a) d = 0.39 (95% CI 20.19 to 0.97), (b) range d = 20.70 to 0.73 (M = 0.25), (c) range d = 0.13 to 0.21 (M = 0.17)

a LMIC status according to the World Bank. ASD, autism spectrum disorder; d, Cohen’s d; ID, intellectual disability; M, mean; QE, quasi-experimental study; RCT, randomized controlled trial; T1, T2, T3, treatment groups for studies with multiple treatments. doi:10.1371/journal.pmed.1001572.t007

Intervention density was directly related to the overall approach, with focal content interventions having relatively low densities of about 2 h per week and whole day curricular approaches typically having densities in excess of 30 h per week. As shown in Figure 10, there is not clear evidence that greater intervention density was related to greater intervention effects, with 50% or fewer estimates for both density categories (#10 h per week and .10 h per week) having effect size estimates greater than 0.50.

with different training and supervisory requirements across studies, delivered interventions. All outcomes addressed using cognitive rehabilitative strategies showed mixed effects, but, as illustrated in Figure 4, developmental and school performance outcomes showed the strongest effects (although only one of the four effect size estimates .0.50, which was statistically significant, was from a study that used a randomized controlled trial design [78]). As shown across tables, the cognitive rehabilitation studies included participants older than 4 y with a mixture of diagnostic history with all levels of intellectual disability. Overall, the cognitive rehabilitation studies had the highest mean participant chronological ages; no studies had a mean age less than 3 y, and seven of nine (78%) studies had mean chronological ages older than 6 y. The cognitive rehabilitation category had the only studies with adolescents in this review [80,82]. As shown in Figures 6 and 7, the results of the studies were mixed across age ranges, with no range showing superior effects over another. Likewise, as shown in Figure 8, the results were also mixed with respect to level of cognitive impairment. Given the small number of studies, compounded by the variability in intervention methods and intervention density, it is difficult to ascertain a true relation between cognitive ability and intervention success. PLOS Medicine | www.plosmedicine.org

Psychosocial interventions delivered using parent training. We located nine studies [86–94] involving 368

children with intellectual disabilities or lower-functioning autism spectrum disorders in which the child’s parents received a parent training intervention delivered by a non-specialist provider. Table 4 provides descriptions of the intervention techniques and intervention density for each study, and Table 8 provides descriptions of the research characteristics and outcomes for each parent training intervention study. Seven of nine studies were randomized controlled trials, and four studies, all randomized controlled trials, were conducted in LMICs [90,91,93,94]. Most studies we located examined parent training interventions that were focused on teaching parents how to provide therapy services 12



Table 8. Research design, results, and effect sizes for parent training intervention studies.

First Author and Year of Publication of Original Study [Reference] Child Diagnosis

Design

Results by Outcome


ASD

RCT

Intervention group showed significantly better symbolic play after treatment compared to control [155,156] (development) and but no difference for parental stress [157] (family)

Unable to calculate effect size because data for groups were combined

Shin 2009 [91]a

ID

RCT

Both treatment and control groups showed gains across time in daily skills [59]; difference not significant

d = 0.09 (95% CI 20.63 to 0.80)

Plant 2007 [88]

ASD, ID

RCT

Both intervention groups had significantly fewer problem behaviors [158] (a) but no differences were found for maternal distress [159–162] (family) (b)

(a) range 0.33 to 0.99 (M = 0.61), (b) range d = 20.30 to 0.82) (M = 0.30)


ID

RCT

Intervention group had significantly better scores for the developmental outcome [39]

d = 1.47 (95% CI 0.65–2.28)

Roberts 2006 [89]

ASD, ID

RCT

Intervention group showed significant decreases in problem behavior [133] (a) and more appropriate parenting techniques [159,161,163] (family) (b)

(a) d = 0.69 (95% CI 0.15–1.24), (b) range d = 0.19 to 1.00 (M = 0.64)

Russell 1999 [90]a

ID

RCT

Intervention group had significantly better scores on all family outcomes except attitude towards intellectual disability, which was unchanged in both groups [164]

Range d = 20.13 to 1.01 (M = 0.61)

Varma 1992 [93]a

ID

RCT

Intervention group had significantly better developmental [165–168] (a), behavioral [169] (b), and family outcomes [164,170,171] (c)

(a) d = 0.63 (95% CI 0.18–1.08), (b) d = 0.54 (95% CI 0.10–1.09), (c) range d = 0.87 to 1.43 (M = 1.15)


ASD, ID

QE

Intervention group had a significantly greater vocabulary [58] (development) (a), but no differences for behavior [172] (b) or family outcomes [135,173] (c)

(a) d = 0.55 (95% CI 20.01– 1.11), (b) d = 0.00 (95% CI 20.55–0.55), (c) range d = 20.53 to 0.05 (M = 20.18)

Shu 2005 [92]

ASD

QE

Statistically significant difference between treatment and control group not found for family outcomes [174,175]

Range d = 22.40 to 0.31 (M = 21.05)

Wong 2010 [94]

a

a LMIC status according to the World Bank. d, Cohen’s d; M, mean; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.t008

to their child; one study [92] focused mostly on improving parental well-being. As shown in Figure 5, the strongest effects were shown in developmental, behavioral, and family outcomes, with each outcome having three effect size estimates greater than 0.50, with many of these outcomes shown in randomized controlled trials [86,88–90,93], and with five of nine of the effect size estimates, all from randomized controlled trials, having statistical significance. As shown in Figures 6 and 7, the parent training interventions were most effective for parents of primary-school-aged children, where all four effect size estimates, three of which were statistically

significant and all of which were from randomized controlled trials, were .0.50 [90,93]. As described across tables and shown across figures, studies of parent training interventions typically included samples that were exclusively children with intellectual disability or studies that were a mixture of children with intellectual disability and lowerfunctioning autism spectrum disorders. The strongest effects were shown for individuals with intellectual disability without autism (five of six effect size estimates .0.50). Given the lack of specificity of child developmental level (five studies did not report a specific

Figure 2. Risk of bias graph. Review authors’ judgments about each risk of bias item, presented as percentages across all included studies. doi:10.1371/journal.pmed.1001572.g002


13



Figure 3. Harvest plot matrix of effect size estimates by outcome category for behavior analytic studies. ASD, autism spectrum disorders; ES, effect size; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.g003

level; see Table 1 and Figure 8), we were unable to draw conclusions about whether parent training interventions were more or less effective for children with mild or more severe levels of intellectual impairment. Likewise, since seven of nine (78%) studies were conducted in clinical settings, comparison of clinicbased and home-based parent training programs was not possible (see Table 5 and Figure 9). Compared to the behavior analytic interventions, the parent training interventions had much lower intervention densities, typically one or two 60- to 120-min sessions per week for 8 to 16 wk (see Table 4). As shown in Figure 10, five of eight (63%) effect size estimates, four of which were statistically significant, and three of six (50%) effect size estimates, one of which was statistically significant, were greater than 0.50 for the lowerdensity (#90 min per week) and higher-density (.90 min per week) categories, respectively. All effect size estimates for the lower-density category came from randomized controlled trials, and three of four large effect size estimates for the PLOS Medicine | www.plosmedicine.org

higher-density category came from randomized controlled trials. Although it does not appear that increased density was systematically related to greater effects, it should be noted that these programs were often provided in conjunction with, not replacing, the child’s typical school or early intervention programming, which complicates our ability to draw definitive conclusions.

Discussion Summary of Main Findings This review shows that there is a range of psychosocial interventions for individuals with intellectual disabilities or lower-functioning autism spectrum disorders that can be provided by non-specialist service providers. Overall, the outcomes of the studies included in this review show that non-specialist providers can deliver effective treatments to children with intellectual disabilities or lower-functioning autism spectrum disorders. As 14



Figure 4. Harvest plot matrix of effect size estimates by outcome category for cognitive rehabilitation, training, and support studies. ASD, autism spectrum disorders; ES, effect size; ID, intellectual disability; MIX, autism spectrum disorders and intellectual disability; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.g004

for parent training interventions, which had seven randomized controlled trials. For the parent training interventions, eight of nine effect size estimates greater than 0.50 were found for developmental, behavioral, and family outcomes, with five of the eight estimates from randomized controlled trials having statistical significance. Although our methods preclude a formal sensitivity analysis, examination of the tall marks in Figures 3–5 (which are representative of studies conducted using a randomized controlled trial design) shows the greatest amount of evidence for developmental and family outcomes for behavior analytic and parent training interventions, and robust findings for behavioral outcomes for parent training interventions. It is also noteworthy that the greatest percentage of studies with randomized controlled trials involved parent training interventions, where seven of nine (78%) studies were conducted using this design. Collectively, our review shows that beneficial effects can be realized when non-specialist providers deliver psychosocial

stated earlier, there was a large range of effect size estimates, from a low of 21.89 to a high of 2.51; a large majority of the effect size estimates were positive (45 of 59, 76%), with just under half (29 of 59, 49%) being greater than 0.50, likely indicating clinically significant effects. Eighteen of the 29 effect size estimates greater than 0.50 were statistically significant across intervention types. For the behavior analytic interventions, the best outcomes were shown for development and daily skills, especially for children with more severe levels of cognitive impairment at treatment onset. Cognitive rehabilitation, training, and support were found to be most effective for improving developmental outcomes in children with intellectual disabilities between 6 and 11 y of age, with mixed effects shown for daily skills and school performance. Finally, we found parent training interventions to be most effective for improving developmental, behavioral, and family outcomes when training was conducted in clinical settings. The strongest evidence from randomized controlled trials was found PLOS Medicine | www.plosmedicine.org

15



Figure 5. Harvest plot matrix of effect size estimates by outcome category for parent training interventions. ASD, autism spectrum disorders; ES, effect size; ID, intellectual disability; MIX, autism spectrum disorders and intellectual disability; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.g005

issues—including (a) the number of hours of training required to learn treatment techniques, (b) the requirements for supervision of treatment providers, (c) the intensity of interventions, and (d) the professional and education backgrounds of the people delivering the intervention—we allow readers to assess the applicability of the evidence about the various psychosocial interventions to the specific context. Our findings that psychosocial interventions can be effective when delivered by non-specialist providers have much relevance for improving access to care for children and adolescents with intellectual disabilities or lower-functioning autism spectrum disorders who live in both HICs and LMICs, but they are especially useful in low-resource settings. These findings have the potential to facilitate an increase in access to psychosocial interventions for persons with developmental disorders by promoting task shifting and human resource development approaches. Within this context, the findings from our review

interventions to children with intellectual disabilities or lowerfunctioning autism spectrum disorders.

Relevance of Findings to Low-Resource Settings The generation of evidence to inform practices in low-resource contexts, and specifically in LMICs, was part of the rationale for this review. We considered many factors during the scoping of the review to ensure that the results could be applied to LMICs, based on previous work by the World Health Organization’s Department of Mental Health and Substance Abuse in developing evidence-based recommendations for LMICs [11,95]. First, we only included studies that reported the outcomes of interventions delivered by non-specialist providers in community-based settings to increase the directness of evidence. All studies about interventions delivered by members of a research team or by specialists were excluded. In addition, by making explicit the information concerning a number of feasibility and contextual PLOS Medicine | www.plosmedicine.org

16



Figure 6. Harvest plot matrix comparison of effects by mean age of participants for children under 6 y old. ASD, autism spectrum disorders; ES, effect size; ID, intellectual disability; MIX, autism spectrum disorders and intellectual disability; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.g006

that are likely to be most relevant are those from the studies that provided therapies with lower treatment density (e.g., psychosocial interventions requiring less than 10 h per week of direct therapy, or parent training interventions that met for 90 min or less per week). Two behavior analytic studies [66,67] and nine cognitive rehabilitation, training, and support studies [75–80,82] had treatment densities under 10 h per week (see Figure 10). Generally, the effects shown in these studies were weaker than our overall findings, the exception being the study by PetersScheffer et al. [67], which delivered 5 to 10 h of applied behavior analysis on top of standard care, and Elwan and el Din [78], Goetz et al. [79], and Perez and Beltran [82], which all showed very strong effects in development or school performance using inclusion and cognitive training, phonological awareness, and individualized instruction, respectively. Five parent training studies [86,88,91–93] had treatment densities of less than 90 min per PLOS Medicine | www.plosmedicine.org

week, with three of five studies showing strong effects [86,88,93]. It is also important to note that many of the studies providing high treatment densities involved significant supervision of the treatment providers that was often done by highly trained professionals (e.g., specialists such as psychiatrists and psychologists). The regularity, duration, and density of supervision were not reported in enough detail and with enough consistency for us to draw conclusions about the possible effects on outcome, but Reichow and Wolery [96] found supervisor training to have a significant relation to outcome in a review of early intensive behavioral intervention for young children with autism spectrum disorders. In addition to the training and supervision needs, it is also important to take into account that providing care to children with developmental disorders can be psychologically demanding, and appropriate support mechanisms for nonspecialist care providers also need to be established. Uncovering 17



Figure 7. Harvest plot matrix comparison of effects by mean age of participants for children 6 y and older. ASD, autism spectrum disorders; ES, effect size; ID, intellectual disability; MIX, autism spectrum disorders and intellectual disability; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.g007

these variables has important and practical implications regarding the feasibility of scaling up these interventions in low-resource settings. A recent review of the most promising procedures used to train paraprofessionals to work with individuals with autism spectrum disorders identified only a small number of studies, and reported the lack of clear training effects [16]. The review suggested that performance feedback can be a potentially effective and efficient means of on-the-job training that requires further research. E-health approaches(i.e., the transfer of health resources and health care by electronic means, including specifically the delivery of information and capacity building to health care providers through the Internet and telecommunications) have the potential to be instrumental in allowing appropriate training and supervision of non-specialist professionals even when resources and the availability of specialists are limited [97]. PLOS Medicine | www.plosmedicine.org

Relation of Findings to Other Reviews To our knowledge, this is the first review of psychosocial interventions delivered by non-specialist providers for children with intellectual disabilities or lower-functioning autism spectrum disorders. Therefore, direct comparisons with extant reviews are not possible. However, there have been reviews of psychosocial interventions for children with autism and other neurodevelopmental disorders delivered by specialist providers. Three relevant recent reviews [17–19] focused specifically on studies conducted in LMICs. They showed that a small number of studies have been conducted examining psychosocial interventions for children with intellectual disabilities or autism spectrum disorders in LMICs, with overall positive effects being shown for the interventions. An extant review on the effectiveness of interventions for child and adolescent mental health problems in primary care showed that there is some evidence that treatment 18



Figure 8. Harvest plot matrix comparison of effects by severity of intellectual disability. ASD, autism spectrum disorders; ES, effect size; ID, intellectual disability; MIX, autism spectrum disorders and intellectual disability; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.g008

non-specialist providers allows our review to remain unique and one on which future reviews can build.

by non-specialist primary health care and community staff is effective, although the number of studies included was limited [98]. Strong findings were shown in our review for behavior analytic techniques, which are supported by many recent reviews [28,99,100]. There have been fewer reviews of what we categorized as cognitive rehabilitation, training, and support; thus, placing our findings in the context of other reviews is difficult. Finally, as with our overall positive findings for parent training interventions, there are a number of reviews suggesting parents are able to learn the skills necessary to deliver therapies to their children and that the children show beneficial effects from these interventions [24,25]. The findings of our review thus complement the findings of other reviews and have strong relevance for improving care for children with developmental disorders or lower-functioning autism spectrum disorders living in low-resource settings. Collectively, we feel that the findings of our review are well in line with the findings across reviews and that our focus on PLOS Medicine | www.plosmedicine.org

Future Directions and Research Although we located many studies, further research is needed to increase the knowledge of the effects of interventions for children with intellectual disabilities or lower-functioning autism spectrum disorders delivered by non-specialist providers to better inform strategies for service and human resource development. First, future studies should aim to use true experimental designs (randomized controlled trials) with high ecological validity to increase confidence in the effects of this class of interventions. Second, research looking at the effectiveness of capacity building strategies (including distance learning and e-health approaches for training and supervision) in improving non-specialists’ ability to deliver psychosocial interventions, and at the quality of care received by children with developmental disorders, is needed. 19



Figure 9. Harvest plot matrix comparison of effects by intervention setting. ASD, autism spectrum disorders; ES, effect size; ID, intellectual disability; MIX, autism spectrum disorders and intellectual disability; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.g009


20



Figure 10. Harvest plot matrix comparison of effect by treatment density. ASD, autism spectrum disorders; ES, effect size; ID, intellectual disability; QE, quasi-experimental study; RCT, randomized controlled trial. doi:10.1371/journal.pmed.1001572.g010

disabilities and lower-functioning autism spectrum disorders in areas with limited resources.

Third, research is needed on delivery strategies and resource requirements for providing psychosocial interventions for developmental disorders in low-resource settings as part of existing primary health care systems. Fourth, research on mediators and moderators of treatment effects is needed to identify the active and necessary components of treatment models [26]. Finally, research in all of these areas conducted specifically in LMICs will be most valuable in informing future care for persons with intellectual PLOS Medicine | www.plosmedicine.org

Limitations Although we took many steps, including protocol registry and use of the PRISMA checklist [20] (see Checklist S1), to ensure our review process limited potential sources of bias, no review is without limitation. One limiting factor of all systematic reviews is the quality 21



efforts for improving outcomes for children with developmental disorders or lower-functioning autism spectrum disorders.

of the included studies. The inclusion of non-randomized trials in and of itself introduces potential bias [31], and thus must be considered a limitation, although recent work has suggested non-randomized studies with high ecological validity can be an important and valid source of evidence [101]. The inclusion of both randomized and non-randomized trials and the variability of intervention techniques and outcomes precluded synthesizing studies statistically, which can also be seen as a limitation. Instead, we chose to present graphical depictions of effect using harvest plots, which highlighted that there was strong support from randomized controlled trials for parent training interventions to improve developmental, behavioral, and family outcomes. With respect to other risks of bias, as shown in Figures 2 and S1, no study was free of all risks of bias, which has potential impacts on the conclusions reached in this review. Of particular concern is the risk of performance bias, which, by the nature of psychosocial interventions, was high across all studies and must be considered a limitation and taken into consideration when interpreting the findings of this review. Another potential limitation is that most of the studies were conducted in North America or Europe, in HICs. Our stated purpose was to develop recommendations for LMICs, and the lack of ecological validity renders this difficult. It should be noted that almost half of the parent training studies were conducted using randomized controlled trials in LMICs, which might provide the most relevant findings from which to draw conclusions. It should also be noted that many of the nonspecialist providers do in fact receive training, e.g., a teacher typically attends a college or university education program and often obtains licensure. However, many of these individuals might not have received the often extensive amounts of training to develop the skills to provide treatments to individuals with intellectual disabilities or lower-functioning autism spectrum disorders that specialist receive. We also cannot rule out the possibility of publication bias, as it was beyond the scope of this project to locate studies published in gray material. We tried to counter this with an extensive search across numerous global and localized databases. Finally, we limited the participant population to individuals who had an intellectual disability, which might limit the generalizability of our results to other populations of individuals with other developmental disorders, including those with higher-functioning autism spectrum disorders.

Supporting Information Checklist S1 PRISMA checklist [20].

(DOC) Figure S1 Risk of bias summary. Review authors’ judgments about each risk of bias item for each included study, where green indicates low risk of bias, yellow indicates unclear risk of bias, and red indicates high risk of bias. (TIF) Table S1 Outcome measures and outcome categories for included studies. (DOCX) Text S1 Sample search strategy for Medline (1946 to week 2 of June 2013), Cumulative Index to Nursing and Allied Health (1981 to 24 June 2013), and Embase (1974 to 24 June 2013). (DOCX)

Search strategy for PsycINFO (1967 to week 3 of June 2012). (DOCX)

Text S2

Text S3 Sample search strategies for African Index Medicus, AFRO Library, and Western Pacific Region Index Medicus. (DOCX) Text S4 Search strategy for Literatura Latino-Americana e do Caribe em Cieˆncias da Sau´de. (DOCX) Text S5 Search strategy for Cochrane Central Register of Controlled Trials (24 June 2013). (DOCX) Text S6 List of excluded studies, with reason.

(DOCX)

Acknowledgments The authors would like to thank Janis Glover, Yale Medical Library, for coordinating the search strategy, Tomas Allen, World Health Organization, for his input on search methods, David Ogilvie and Mark Crowther for providing templates for the harvest plots, Dana Apkon, Washington University, for her assistance extracting data, and Allison Shefcyk, University of Connecticut Health Center, for her assistance with manuscript and figure preparation.

Conclusion The findings of this review support the delivery of psychosocial interventions by non-specialist providers to children who have intellectual disabilities or lower-functioning autism spectrum disorders. For the behavior analytic interventions, the best outcomes were shown for development and daily skills; cognitive rehabilitation, training, and support were found to be most effective for improving developmental outcomes, and parent training interventions to be most effective for improving developmental, behavioral, and family outcomes. We also conducted additional subgroup analyses using harvest plots. Given the scarcity of specialists in many low-resource settings, including many LMICs, these findings may provide guidance for scale-up

Author Contributions Conceived and designed the review: BR CS MTY CB SS. Performed the review: BR CS CB. Analyzed the data: BR CS MTY CB SS. Contributed reagents/materials/analysis tools: BR CS MTY CB SS. Wrote the first draft of the manuscript: BR CS. Contributed to the writing of the manuscript: BR CS MTY CB SS. ICMJE criteria for authorship read and met: BR CS MTY CB SS. Agree with manuscript results and conclusions: BR CS MTY CB SS.

References 3. Maulik PK, Mascarenhas MN, Mathers CD, Dua T, Saxena S (2011) Prevalence of intellectual disability: a meta-analysis of population-based studies. Res Dev Disabil 32: 419–436. 4. Murray PJL, Vos T, Lozano R, Naghavi M, Flaxman AD, et al. (2012) Disability-adjusted life years (DALYs) for 291 diseases and injuries in 21 regions, 1990–2010: a systematic analysis for the Global Burden of Disease Study 2010. Lancet 380: 2197–2223.

1. World Health Organization (1992) The international classification of diseases. Geneva: World Health Organization. 2. Totsika V, Hastings R, Emerson E, Lancaster G, Berridge D (2011) A population-based investigation of behavioral and emotional problems and maternal mental health: associations with autism spectrum disorder and intellectual disability. J Child Psychol Psychiatry 52: 91– 99.


22



35. Crowther M, Avenell A, MacLennan G, Mowatt G (2011) A further use for the harvest plot: a novel method for the presentation of data syntheses. Res Synth Methods 2: 79–83. 36. Ogilivie D, Fayter D, Petticrew M, Sowden A, Thomas S, et al. (2008) The harvest plot: a method for synthesizing evidence about the differential effects of interventions. BMC Med Res Methodol 25: 8. 37. Mullen EM (1995) Mullen scales of early learning: AGS edition. Circle Pines (Minnesota): American Guidance Service. 38. Bayley N (1993) Bayley scales of infant development, 2nd edition. San Antonio (Texas): The Psychological Corporation. 39. Brunet O, L’ezine I (1955) Echelle de developpement psychomoteur de la premiere enfance. Clamart (France): Editions Scientifiques et Psychotechniques. 40. Alpern G, Boll T, Shearer M (1986) Developmental profile II (DP-II). Los Angeles (California): Western Psychological Services. 41. Thorndike RL, Hagen EP, Sattler JM (1986) The Stanford-Binet intelligence scale, 4th edition. Chicago (Illinois): Riverside. 42. Stutsman R (1948) Merrill Palmer scale of mental tests. Wood Dale (Illinois): Stoelting. 43. Elliott C (1990) The DAS administration and scoring manual. San Antonio (Texas): The Psychological Corporation. 44. Schopler E, Reichler RJ, Bashford A, Lansing MD, Marcus LM (1990) The psychoeducational profile–revised (PEP-R). Austin (Texas): PRO-ED. 45. Wechsler D (1989) Wechsler preschool and primary scale of intelligence– revised. San Antonio (Texas): The Psychological Corporation. 46. Voress JK, Maddox T (1998) Developmental assessment of young children. Austin (Texas): PRO-ED. 47. Roid G, Miller L (1997) Leiter international performance scale–revised. Wood Dale (Illinois): Stoelting. 48. Reynell JK, Gruber GP (1990) Reynell developmental language scales. Los Angeles (California): Western Psychological Services. 49. Dunn LM, Dunn DM (1997) Peabody picture vocabulary test, 3rd edition. Circle Pines (Minnesota): American Guidance Service. 50. Rossetti L (1990) The Rossetti Infant-Toddler Language Scale: a measure of communication and interaction. East Moline (Illinois): Linguisystems. 51. Bzoch K, League R (1991) Receptive expressive emergent language scales– revised (REEL-2). Austin (Texas): PRO-ED. 52. Zimmerman IL, Steiner VG, Pond RE (1992) The preschool language scale–3. San Antonio (Texas): The Psychological Corporation. 53. Provence S, Eriksen J, Vater S, Palmeri S (1985) Infant toddler developmental assessment. Chicago (Illinois): Riverside Publishing. 54. Hendrick D, Prather E, Tobin A (1984) Sequenced inventory of communication development–revised edition. Seattle (Washington): University of Washington Press. 55. Brownell R (2000) Expressive one-word picture vocabulary test. Novato (California): Academic Therapy. 56. Brownell R (2000) Receptive one-word picture vocabulary test. Novato (California): Academic Therapy. 57. Mundy P, Hogan A, Dohering P (1996) A preliminary manual for the abridged Early Social Communication Scales. Coral Gables (Florida): University of Miami. 58. Fenson L, Dale PS, Reznick JS, Bates E, Thal D (1993) MacArthur Communicative Development Inventories: user’s guide and technical manual. San Diego: Singular Publishing Group. 59. Sparrow SS, Balla DA, Cicchetti DV (1984) The Vineland adaptive behavior scales–interview edition. Circle Pines (Minnesota): American Guidance Service. 60. Cohen H, Amerine-Dickens M, Smith T (2006) Early intensive behavioral treatment: replication of the UCLA model in a community setting. J Dev Behav Pediatr 27: S145–S155. 61. Dawson G, Rogers S, Munson J, Smith M, Winter J, et al. (2010) Randomized, controlled trial of an intervention for toddlers with autism: the Early Start Denver Model. Pediatrics 125: e17–e23. 62. Eikeseth S, Smith T, Jahr E, Eldevik S (2007) Outcome for children with autism who began intensive behavioral treatment between ages 4 and 7: a comparison controlled study. Behav Modif 31: 264–278. 63. Eikeseth S, Klintwall L, Jahr E, Karlsson P (2012) Outcome for children with autism receiving early and intensive behavioral intervention in mainstream preschool and kindergarten settings. Res Autism Spectr Disord 6: 829–835. 64. Howard JS, Sparkman CR, Cohen HG, Green G, Stanislaw H (2005) A comparison of intensive behavior analytic and eclectic treatments for young children with autism. Res Dev Disabil 26: 359–383. 65. Jocelyn LJ, Casiro OG, Beattie D, Bow J, Kneisz J (1998) Treatment of children with autism: a randomized controlled trial to evaluate a caregiverbased intervention program in community day-care centers. J Dev Behav Pediatr 19: 326–334. 66. Kaale A, Smith L, Sponheim E (2012) A randomized controlled trial of preschool-based joint attention intervention for children with autism. J Child Psychol Psychiatry 53: 97–105. 67. Peters-Scheffer N, Didden R, Mulders M, Korzilius H (2010) Low intensity behavioral treatment supplementing preschool services for young children with autism spectrum disorders and severe to mild intellectual disability. Res Dev Disabil 31: 1678–1684. 68. Reed P, Osborne LA, Corness M (2007) Brief report: relative effectiveness of different home-based behavioral approaches to early teaching intervention. J Autism Dev Disord 37: 1815–1821.

5. Kieling C, Baker-Henningham H, Belfer M, Conti G, Ertem I, et al. (2011) Child and adolescent mental health worldwide: evidence for action. Lancet 378: 1515–1525. 6. Demyttenaere K, Bruffaerts R, Posada-Villa J, Gasquet I, Kovess V, et al. (2004) Prevalence, severity, and unmet need for treatment of mental disorders in the World Health Organization World Mental Health Surveys. JAMA 291: 2581–2590. 7. World Health Organization (2007) Atlas: global resources for persons with intellectual disabilities. Geneva: World Health Organization. 8. Eaton J, McCay L, Semrau M, Chatterjee S, Baingana F, et al. (2011) Scale up of services for mental health in low-income and middle-income countries. Lancet 378: 1592–1603. 9. Patel V, Goel DS, Desai R (2009) Scaling up services for mental and neurological disorders in low-resource settings. Int Health 1: 37. 10. World Health Organization (2011) Mental health atlas 2011. Geneva: World Health Organization. 11. Dua T, Barbui C, Clark N, Fleischmann A, Poznyak V, et al. (2011) Evidencebased guidelines for mental, neurological, and substance use disorders in lowand middle-income countries: Summary of WHO recommendations. PLoS Med 8: e1001122. doi:10.1371/journal.pmed.1001122 12. Patel V, Kieling C, Maulik PK, Divan G (2013) Improving access to care for children with mental disorders: a global perspective. Arch Dis Child 98: 323– 327. 13. Collins PY, Patel V, Joestle SS, March D, Insel TR, et al. (2011) Grand challenges in global mental health. Nature 475: 27–30. 14. Flisher AJ, Sorsdahl K, Hatherill S, Chehil S (2010) Packages of care for attention-deficit hyperactivity disorder in low- and middle-income countries. PLoS Med 7: e1000235. doi:10.1371/journal.pmed.1000235. 15. Rahman A, Malik A, Sikander S, Roberts C, Creed F (2008) Cognitive behaviour therapy-based intervention by community health workers for mothers with depression and their infants in rural Pakistan: a clusterrandomised controlled trial. Lancet 372: 902–909. 16. Rispoli M, Neely L, Lang R, Ganz JB (2011) Training paraprofessionals to implement interventions for people with autism spectrum disorders: a systematic review. Dev Neurorhabil 14: 378–388. 17. Hastings RP, Robertson J, Yasamy MT (2012) Interventions for children with pervasive developmental disorders in low and middle income countries. J Appl Res Intellect Disabil 25: 119–134. 18. Einfeld SL, Stancliffe RJ, Gray KM, Sofronoff K, Rice L, et al. (2012) Interventions provided by parents for children with intellectual disabilities in low and middle income countries. J Appl Res Intellect Disabil 25: 135–142. 19. Robertson J, Emerson E, Hatton C, Yasamy MT (2012) Efficacy of community-based rehabilitation for children with or at significant risk of intellectual disabilities in low-and middle-income countries: a review. J Appl Res Intellect Disabil 25: 143–154. 20. Moher D, Liberati A, Tetzlaff J, Altman DG (2009) Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Med 6: e1000097. doi:10.1371/journal.pmed.1000097. 21. Sterne JAC, Egger M, Moher D (2008) Addressing reporting biases. In: Higgins JPT, Green S, editors. Cochrane handbook for systematic reviews of interventions. Chichester (UK): John Wiley & Sons. pp. 297–333. 22. Diggle TTJ, McConachie HHR (2002) Parent-mediated early intervention for young children with autism spectrum disorder. Cochrane Database Syst Rev 2002: CD003496. 23. Grey IM, Hastings RP (2005) Evidence-based practices in intellectual disability and behaviour disorders. Curr Opin Psychiatry 18: 469–475. 24. Matson JL, Mahan S, LoVullo SV (2009) Parent training: a review of methods for children with developmental disabilities. Res Dev Disabil 30: 961–968. 25. McConachie H, Diggle T (2007) Parent implemented early intervention for young children with autism spectrum disorder: a systematic review. J Eval Clin Pract 13: 120–129. 26. Odom SL, Boyd BA, Hall LJ, Hume K (2010) Evaluation of comprehensive treatment models for individuals with autism spectrum disorders. J Autism Dev Disord 40: 425–436. 27. Reichow B (2012) Overview of reviews: early intensive behavioral interventions for children with autism spectrum disorders. J Autism Dev Disord 42: 512–520. 28. Rogers SJ, Vismara LA (2008) Evidence-based comprehensive treatments for early autism. J Clin Child Adolesc Psychol 37: 8–38. 29. Higgins JPT, Altman DG (2008) Assessing risk of bias in included studies. In: Higgins JPT, Green S, editors. Cochrane handbook for systematic reviews of interventions. Chichester (UK): John Wiley & Sons. 30. Reeves BC, Deeks JJ, Higgins JPT, Wells GA (2008) Including non-randomized studies. In: Higgins JPT, Green S, editors. Cochrane handbook of systematic reviews of interventions. Chichester (UK): John Wiley & Sons. 31. Reeves BC, Higgins JPT, Ramsay C, Shea B, Tugwell P, et al. (2013) An introduction to methodological issues when including non-randomised studies in systematic reviews on the effects of interventions. Res Synth Methods 4: 1– 11. 32. Lipsey MW, Wilson DB (2001) Practical meta-analysis. Thousand Oaks (California): Sage. 33. Cohen J (1988) Statistical power analysis for the behavioral sciences, 2nd edition. Hillsdale (New Jersey): Lawrence Erlbaum Associates. 34. Borenstein M, Hedges LV, Higgins JPT, Rothstein HR (2009) Introduction to meta-analysis. Chichester (UK): John Wiley & Sons.


23



69. Remington B, Hastings RP, Kovshoff H, degli Espinosa F, Jahr E, et al. (2007) Early intensive behavioral intervention: outcomes for children with autism and their parents after two years. Am J Ment Retard 112: 418–438. 70. Smith T, Groen AD, Wynn JW (2000) Randomized trial of intensive early intervention for children with pervasive developmental disorder. Am J Ment Retard 105: 269–285. 71. Dawson G, Jones EJH, Merkle K, Venema K, Lowy R, et al. (2012) Early behavioral intervention is associated with normalized brain activity in young children with autism. J Am Acad Child Adolesc Psychiatry 51: 1150–1159. 72. Eikeseth S, Smith T, Jahr E, Eldevik S (2002) Intensive behavioral treatment at school for 4- to 7-year-old children with autism: a 1-year comparison controlled study. Behav Modif 26: 49–68. 73. Grindle CF, Hastings RP, Saville M, Hughes JC, Huxley K, et al. (2012) Outcomes of a behavioral education model for children with autism in a mainstream school setting. Behav Modif 36: 298–319. 74. Baer DM, Wolf MM, Risley TR (1968) Some current dimensions of applied behavior analysis. J Appl Behav Anal 1: 91–97. 75. Allor JH, Mathes PG, Roberts J, Cheatham JP, Champlin TM (2010) Comprehensive reading instruction for students with intellectual disabilities: findings from the first three years of a longitudinal study. Psychol Sch 47: 445– 466. 76. Browder D, Ahlgrim-Delzell L, Flowers C, Baker J (2012) An evaluation of a multicomponent early literacy program for students with severe developmental disabilities. Remedial Spec Educ 33: 237–246. 77. Burgoyne K, Duff FJ, Clarke PJ, Buckley S, Snowling MJ, et al. (2012) Efficacy of a reading and language intervention for children with Down syndrome: a randomized controlled trial. J Child Psychol Psychiatry 53: 1044–1053. 78. Elwan F, el Din MN (2010) Impact of integration and a cognitive training program on basic cognitive processes among Egyptian preschoolers with Down syndrome. Dev Disabil Bull 38: 1–19. 79. Goetz K, Hulme C, Brigstocke S, Carroll JM, Nasir L, et al. (2008) Training reading and phoneme awareness skills in children with Down syndrome. Read Writ 21: 395–412. 80. Jepsen RH, VonThaden K (2002) The effect of cognitive education on the performance of students with neurological developmental disabilities. Neurorehabil 17: 201–209. 81. Panerai S, Zingale M, Trubia G, Finocchiaro M, Zuccarello R, et al. (2009) Special education versus inclusive education: the role of the TEACCH Program. J Autism Dev Disord 39: 874–882. 82. Perez LF, Beltran JAJA (2008) A Spanish intervention programme for students with special education needs: effects on intellectual capacity and academic achievement. Eur J Spec Needs Educ 23: 147–156. 83. Tsang SK, Shek DT, Lam LL, Tang FL, Cheung PM (2007) Brief report: application of the TEACCH program on Chinese pre-school children with autism—does culture make a difference? J Autism Dev Disord 37: 390–396. 84. Allor JH, Mathes PG, Roberts J, Jones FG, Champlin TM (2010) Teaching students with moderate intellectual disabilities to read: an experimental examination of a comprehensive reading intervention. Educ Train Autism Dev Disabil 45: 3–22. 85. Browder DM, Ahlgrim-Delzell L, Courtade G, Gibbs SL, Flowers C (2008) Evaluation of the effectiveness of an early literacy program for students with significant developmental disabilities. Except Child 75: 33–52. 86. Del Giudice E, Titomanlio L, Brogna G, Bonaccorso A, Romano A, et al. (2006) Early intervention for children with Down syndrome in Southern Italy: the role of parent-implemented developmental training. Infants Young Child 19: 50–58. 87. McConachie H, Randle V, Hammal D, Le Couteur A (2005) A controlled trial of a training course for parents of children with suspected autism spectrum disorder. J Pediatrics 147: 335–340. 88. Plant KM, Sanders MR (2007) Reducing problem behavior during care-giving in families of preschool-aged children with developmental disabilities. Res Dev Disabil 28: 362–385. 89. Roberts C, Mazzucchelli T, Studman L, Sanders MR (2006) Behavioral family intervention for children with developmental disabilities and behavioral problems. J Clin Child Adolesc Psychol 35: 180–193. 90. Russell PS, al John JK, Lakshmanan JL (1999) Family intervention for intellectually disabled children. Randomised controlled trial. Br J Psychiatry 174: 254–258. 91. Shin J, Nhan N, Lee S, Crittenden K, Flory M, et al. (2009) The effects of a home-based intervention for young children with intellectual disabilities in Vietnam. J Intellect Disabil Res 53: 339–352. 92. Shu BC, Lung FW (2005) The effect of support group on the mental health and quality of life for mothers with autistic children. J Intellect Disabil Res 49: 47– 53. 93. Varma VK, Verma SK, Kapoor P (1992) Evaluation of a home care programme for the mentally retarded children through training of the mother. Indian J Med Res 96: 29–36. 94. Wong VC, Kwan QK (2010) Randomized controlled trial for early intervention for autism: a pilot study of the Autism 1-2-3 project. J Autism Dev Disord 40: 677–688. 95. Barbui C, Dua T, van Ommeren M, Yasamy MT, Fleischman A, et al. (2010) Challenges in developing evidence-based recommendations using the GRADE apprach: the case of mental, neurological, and substance use disorders. PLoS Med 7: e1000322. doi:10.1371/journal.pmed.1000322.


96. Reichow B, Wolery M (2009) Comprehensive synthesis of early intensive behavioral interventions for young children with autism based on the UCLA young autism project model. J Autism Dev Disord 39: 23–41. 97. Boisvert M, Lang R, Andrianopoulos M, Boscardin ML (2010) Telepractice in the assessment and treatment of individuals with autism spectrum disorders. Dev Neurorhabil 13: 423–432. 98. Bower P, Garralda E, Kramer T, Harrington R, Sibbald B (2001) The teatment of child and adolescent mental health problems in primary care: a systematic review. Fam Pract 18: 373–382. 99. Reichow B, Barton EE, Boyd BA, Hume K (2012) Early intensive behavioral intervention (EIBI) for young children with autism spectrum disorders (ASD). Cochrane Database Syst Rev 2012: CD009260. 100. Eldevik S, Hastings RP, Hughes JC, Jahr E, Eikeseth S, et al. (2009) Metaanalysis of Early Intensive Behavioral Intervention for children with autism. J Clin Child Adolesc Psychol 38: 439–450. 101. Schunemann HJ, Tugwell P, Reeves BC, Ekl EA, Santesso N, et al. (2013) Non-randomized studies as a source of complementary, sequential, or replacement evidence for randomized controlled trials in systematic reviews on the effects of interventions. Res Synth Methods 4: 49–62. 102. Kasari C, Freeman S, Paparella T (2006) Joint attention and symbolic play in young children with autism: a randomized controlled intervention study. J Child Psychol Psychiatry 47: 611–620. 103. Rogers SJ, Dawson G (2009) Early Start Denver Model for young children with autism. New York: Guilford. 104. Lovaas OI (1981) Teaching developmentally disabled children: the me book. Baltimore: University Park. 105. Lovaas OI (2003) Teaching individuals with developmental delays: basic intervention techniques. Austin (Texas): PRO-ED. 106. Greer RD (1997) The comprehensive application of behavior analysis to schooling (CABAS[R]). Behav Soc Issues 7: 59–63. 107. Sundberg ML, Michael J (2001) The benefits of Skinner’s analysis of verbal behavior for children with autism. Behav Modif 25: 698–724. 108. Green G, Brennan LC, Fein D (2002) Intensive behavioral treatment for a toddler at high risk for autism. Behav Modif 26: 69–102. 109. Maurice C, Green G, Luce S (1996) Behavioral intervention for young children with autism: a manual for parents and professionals. Austin (Texas): PRO-ED. 110. Maurice C, Green G, Foxx RM (2001) Making a difference: behavioral intervention for autism. Austin (Texas): PRO-ED. 111. Browder D, Gibbs S, Ahlgrim-Delzell L, Courtade G, Lee A (2007) Early literacy skills builder. Verona (Wisconsin): Attainment Company. 112. Mathes PG, Torgensen JK (2005) Early interventions in reading. Columbus (Ohio): SRA/McGraw-Hill. 113. Mesibov GB, Shea VS, Schopler E (2005) The TEACCH approach to autism spectrum disorders. New York: Springer. 114. Lloyd S (1998) The phonics handbook, 3rd edition. Chigwell (UK): Jolly Learning. 115. Hatcher PJ, Hulme C, Ellis AW (1994) Ameliorating early reading failure by integrating teaching of reading and phonological skills: the phonological linkage hypothesis. Child Dev 65: 820–827. 116. Gardner H (1983) Frames of mind: the theory of multiple intelligences. New York: Basic Books. 117. Anderson LW, Krathwohl DRE (2001) A taxonomy for learning, teaching, and assessing: a revision of Bloom’s taxonomy of educational objectives. New York: Longman. 118. CESA 5 (2003) Portage guide birth to six: activities and routines for preschoolers. Portage (Wisconsin): CESA 5. 119. Sanders MR (1999) Triple P–Positive Parenting Program: towards an empirically validated multilevel parenting and family support strategy for the prevention of behavior and emotional problems in children. Clin Child Fam Psychol Rev 2: 71–90. 120. Sanders MR, Mazzucchelli TG, Studman LJ (2003) Practitioner’s manual for standard Stepping Stones Triple P. Brisbane (Australia): Triple P International. 121. Sussman F (1999) More than words: helping parents promote communication and social skills in children with autism spectrum disorder. Toronto: Hanen Centre. 122. Bodfish JW, Symons FJ, Lewis MH (1998) The Repetitive Behavior Scale: a test manual. Morgantown (North Carolina): Western Carolina Research Reports. 123. Bayley N (1969) Bayley scales of infant development. New York: Psychological Corporation. 124. Smith T (1990) Family Satisfaction Questionnaire [unpublished instrument]. Pullman (Washington): Washington State University Department of Psychology. 125. Achenbach TM (1991) Integrative guide for the Child Behavior Checklist L/418 YSR, and Teacher Report Form profiles. Burlington (Vermont): University of Vermont Department of Psychiatry. 126. Schafer DS, Moersch MS (1981) Developmental programming for infants and young children. Ann Arbor (Michigan): University of Michigan Press. 127. Krug DA, Arick J, Almond P (1980) Behavior checklist for identifying severely handicapped individuals with high levels of autistic behavior. J Child Psychol Psychiatry 21: 221–229. 128. Skinner HA, Steinhauer PD, Santa-Barbara J (1983) The family assessment measure. Can J Commun Ment Health 2: 91–105.

24



154. Woodcock RW, Mather N (1989) Woodcock-Johnson psychoeducational battery–revised. Allen (Texas): DLM Teaching Resources. 155. Lowe M, Costello A (1988) Symbolic play test manual, 2nd edition. London: NFER-Nelson. 156. Freeman BJ, Ritvo ER, Yokota A, Ritvo A (1986) A scale for rating symptoms of patients with the syndrome of autism in real life settings. J Am Acad Child Psychiatry 25: 130–136. 157. Abidin R (1995) Parenting stress index: professional manual. Odessa (Florida): Psychological Assessment Resources. 158. Eyberg SM, Pincus D (1999) Eyberg child behavior inventory and SutterEyberg student behavior inventory-revised: professional manual. Odessa (Florida): Psychological Assessment Resources. 159. Arnold DS, O’Leary SG, Wolff LS, Acker MM (1993) The Parenting Scale: a measure of dysfunctional parenting in discipline situations. Psychol Assess 5: 137–144. 160. Gibaud-Wallston J, Wandersman LP (1978) Development and utility of the Parenting Sense of Competency Scale [abstract]. 86th Annual Convention of the American Psychological Association; September 1978; Toronto, Ontario, Canada. 161. Lovibond SH, Lovibond PF (1995) Manual for the depression anxiety stress scales, 2nd edition. Sydney (Australia): Psychology Foundation of Australia. 162. Sharpley CF, Rogers HJ (1984) Preliminary validation of the abbreviated Spanier Dyadic Adjustment Scale: some psychometric data regarding a screening test of marital adjustment. Educ Psychol Meas 44: 1045–1049. 163. Sanders MR, Waugh L, Tully L, Hynes K (1996) The revised family observation schedule, 3rd edition. Brisbane (Australia): Parenting and Family Support Centre. 164. Bhatti RS, Chanabasavanna SM, Prabhu LR (1985) A tool to study of parents towards the management of mentally retarded children. Child Psychiatry Q 18: 1–8. 165. Malin AJ (1969) Malin’s intellegence scale for Indian children. Nagpur (India): Child Guidance Center. 166. Verma SK, Pershad D, Kaushai P (1972) Gessell’s drawing tests as a measure of intelligence in the mentally retarded children. Indian J Ment Retard 5: 64– 68. 167. Verma SK, Pershad D, Randhawa AA (1979) A normative study of children’s performance tests of intelligence. Chandigarh (India): Postgraduate Institute of Medical Education and Research. 168. Malin AJ (1968) Vineland social maturity scale: Indian adaptation. Nagpur (India): Child Guidance Center. 169. Bhat VK, Sinah AK (1978) A rating scale for child behavior: validation of the Hindi version. Indian J Clin Psychol 5: 25–28. 170. Bhat VK, Gauba S (1978) A marital adjustment questionnaire in Hindi. Indian J Clin Psychol 5: 29–32. 171. Pai S, Kapur RL (1981) The burden on the family of a psychiatric patient: development of an interview schedule. Br J Psychiatry 138: 332–335. 172. Richmond N, Graham P (1971) A behavioral screening questionnaire for use with three-year-old children: preliminary findings. J Child Psychol Psychiatry 12: 5–33. 173. Judson SL, Burden RL (1980) Towards a tailored measure of parental attitudes: an approach to the evaluation of one aspect of intervention projects with parents of handicapped children. Child Care Health Dev 6: 47–55. 174. Cheng TA, Williams P (1986) The design and development of a screening questionnaire (CHQ) for use in community studies of mental disorders in Taiwan. Psychol Med 16: 415–422. 175. Yao G, Chung CW, Yu CF, Wang JD (2002) Development and verification of validity and reliability of the WHOQOL-BREF Taiwan version. J Formos Med Assoc 101: 342–351.

129. MacKay C, Cox T, Burrows G, Lazzerini T (1978) An inventory for the measurement of self-reported stress and arousal. Br J Soc Clin Psychol 17: 283– 284. 130. Wechsler D (1974) Wechsler intelligence test for children–revised. San Antonio (Texas): The Psychological Corporation. 131. Elliot CD, Smith P, McCulloch K (1996) British ability scales, 2nd edition. London: NFER-Nelson. 132. Tasse M, Aman MG, Hammer D, Rojahn J (1996) The Nisonger Child Behavior Rating Form: age and gender effects and norms. Res Dev Disabil 7: 59–75. 133. Einfeld SL, Tonge BJ (2002) Manual for the Developmental Behaviour Checklist, 2nd edition. Melbourne (Australia): University of New South Wales School of Psychiatry. 134. Zigmond AS, Snaith PR (1983) The hospital anxiety and depression scale. Acta Psychiatr Scand 63: 361–370. 135. Friedrich WN, Greenberg MT, Crnic K (1983) A short form of the Questionnaire on Resources and Stress. Am J Ment Defic 88: 41–48. 136. Behr SK, Murphy DL, Summers JA (1992) User’s manual: Kansas Inventory of Parental Perceptions (KIPP). Lawrence (Kansas): University of Kansas Beach Center on Families and Disability. 137. Frankenburg WK (1996) Denver II. Denver Developmental Materials. Denver (Colorado): Denver Developmental Materials. 138. Project RHISE (1979) Rockford Infant Development Evaluation Scales. Bensenville (Illinois): Scholastic Testing Services. 139. Ahlgrim-Delzell L, Browder DM, Flowers C, Baker JN (2008) The nonverbal literacy assessment [abstract]. National Association of School Psychologists 2008 Annual Convention; February 2008; New Orleans, Louisiana, US. 140. Williams KT (1997) Expressive vocabulary test. Circle Pines (Minnesota): American Guidance Service. 141. Hulme C, Stothard SE, Clarke P, Bowyer-Crane C, Harrington A, et al. (2009) York assessment of reading for comprehension: early reading. London: GL Assessment. 142. Renfrew C (1997) Action picture test. Milton Keynes (UK): Speechmark. 143. Woodcock RW (1991) Woodcock language proficiency battery–revised. Rolling Meadows (Illinois): Riverside Publishing. 144. Wagner R, Torgesen J, Rashotte C (1999) Comprehensive test of phonological processing. Austin (Texas): PRO-ED. 145. Torgesen JK, Wagner RK, Rashotte CA (1999) The test of word reading efficiency. Austin (Texas): PRO-ED. 146. Kaufman AS, Kaufman NL (1983) Kaufman assessment battery for children, interpretative. Circle Pines (Minnesota): American Guidance Service. 147. McCarthy DA (1972) Manual for the McCarthy scales of children’s abilities. New York: The Psychological Corporation. 148. Carroll JM, Snowling MJ (2001) The effects of global similarity between stimuli on children’s judgment of rime and alliteration. Appl Psycholinguist 22: 327–342. 149. Clay M (1985) The early detection of reading difficulties, 3rd edition. Tadworth (UK): Heinemann. 150. Shek DTL, Tsang SKM, Lam LL, Tang FLY, Cheung PMP (2005) Psychometric properties of the Chinese version of the Psycho-Educational Profile-Revised (CPEP-R). J Autism Dev Disord 35: 37–44. 151. Kwok J, Shek DTL, Tse J, Chan S (1989) Hong Kong based adaptive behavior scale. Hong Kong: City Polytechnic of Hong Kong Department of Applied Social Studies. 152. Das JP, Naglieri JA (1997) Cognitive assessment system (CAS). Itasca (Illinois): Riverside Publishing Company. 153. Nihira K, Foster R, Shellhaas M, Leland H (1975) AAMD adaptive behavior scale–revised. Washington (District of Columbia): American Association on Mental Deficiency.


25



Editors’ Summary were seen for development and daily skills. Cognitive rehabilitation, training, and support (interventions that facilitates the relearning of lost or altered cognitive skills) produced good improvements in developmental outcomes such as standardized IQ tests in children aged 6–11 years old. Finally, parental training interventions (which teach parents how to provide therapy services for their child) had strong effects on developmental, behavioral, and family outcomes.

Background. Newborn babies are helpless, but over the first few years of life, they acquire motor (movement) skills, language (communication) skills, cognitive (thinking) skills, and social (interpersonal interaction) skills. Individual aspects of these skills are usually acquired at specific ages, but children with a development disorder such as an autism spectrum disorder (ASD) or intellectual disability (mental retardation) fail to reach these ‘‘milestones’’ because of impaired or delayed brain maturation. Autism, Asperger syndrome, and other ASDs (also called pervasive developmental disorders) affect about 1% of the UK and US populations and are characterized by abnormalities in interactions and communication with other people (reciprocal socio-communicative interactions; for example, some children with autism reject physical affection and fail to develop useful speech) and a restricted, stereotyped, repetitive repertoire of interests (for example, obsessive accumulation of facts about unusual topics). About half of individuals with an ASD also have an intellectual disability—a reduced overall level of intelligence characterized by impairment of the skills that are normally acquired during early life. Such individuals have what is called lowerfunctioning ASD.

What Do These Findings Mean? Because few of the studies included in this systematic review were undertaken in low- and middle-income countries, the review’s findings may not be generalizable to children living in resourcelimited settings. Moreover, other characteristics of the included studies may limit the accuracy of these findings. Nevertheless, these findings support the delivery of psychosocial interventions by non-specialist providers to children who have intellectual disabilities or a lower-functioning ASD, and indicate which interventions are likely to produce the largest improvements in developmental, behavioral, and family outcomes. Further studies are needed, particularly in low- and middle-income countries, to confirm these findings, but given that specialists are scarce in many resource-limited settings, these findings may help to inform the implementation of programs to improve outcomes for children with intellectual disabilities or lower-functioning ASDs in low- and middle-income countries.

Why Was This Study Done? Most of the children affected by developmental disorders live in low- and middle-income countries where there are few services available to help them achieve their full potential and where little research has been done to identify the most effective treatments. The development of effective treatments for use by nonspecialists (for example, teachers and parents) is necessary to improve the lives of people with mental illnesses worldwide, but particularly in resource-limited settings where psychiatrists, psychologists, and other specialists are scarce. In this systematic review, the researchers investigated which psychosocial interventions for children and adolescents with intellectual disabilities or lower-functioning ASDs delivered by non-specialist providers in community settings produce improvements in development, daily skills, school performance, behavior, or family outcomes when compared to usual care (the control condition). A systematic review identifies all the research on a given topic using predefined criteria; psychosocial interventions are defined as therapy, education, training, or support aimed at improving behavior, overall development, or specific life skills without the use of drugs.

Additional Information. Please access these websites via the online version of this summary at http://dx.doi.org/10. 1371/journal.pmed.1001572.

N N N N N

What Did the Researchers Do and Find? The researchers identified 29 controlled studies (investigations with an intervention group and a control group) that examined the effects of various psychosocial interventions delivered by non-specialist providers to children (under 18 years old) who had a lower-functioning ASD or intellectual disability. The researchers retrieved information on the participants, design and methods, findings, and intervention characteristics for each study, and calculated effect sizes—a measure of the effectiveness of a test intervention relative to a control intervention—for several outcomes for each intervention. Across the studies, three-quarters of the effect size estimates were positive, and nearly half were greater than 0.50; effect sizes of less than 0.2, 0.2–0.5, and greater than 0.5 indicate that an intervention has no, a small, or a medium-to-large effect, respectively. For behavior analytic interventions (which aim to improve socially significant behavior by systematically analyzing behavior), the largest effect sizes


N N N

26

This study is further discussed in a PLOS Medicine Perspective by Bello-Mojeed and Bakare The US Centers for Disease Control and Prevention provides information (in English and Spanish) on developmental disabilities, including autism spectrum disorders and intellectual disability The US National Institute of Mental Health also provides detailed information about autism spectrum disorders, including the publication ‘‘A Parent’s Guide to Autism Spectrum Disorder’’ Autism Speaks, a US non-profit organization, provides information about all aspects of autism spectrum disorders and includes information on the Autism Speaks Global Autism Public Health Initiative The National Autistic Society, a UK charity, provides information about all aspects of autism spectrum disorders and includes personal stories about living with these conditions The UK National Health Service Choices website has an interactive guide to child development and information about autism and Asperger syndrome, including personal stories, and about learning disabilities The UK National Institute for Health and Care Excellence provides clinical guidelines for the management and support of children with autism spectrum disorders The World Health Organization provides information on its Mental Health Gap Action Programme (mhGAP), which includes recommendations on the management of developmental disorders by non-specialist providers; the mhGAP Evidence Resource Center provides evidence reviews for parent skills training for management of



N

children with intellectual disabilities and pervasive developmental disorders and interventions for management of children with intellectual disabilities


27

PROSPERO, an international prospective register of systematic reviews, provides more information about this systematic review


PRISMA 2009 Checklist #

Checklist item

Reported on page #

1

Identify the report as a systematic review, meta-analysis, or both.

page 1

2

Provide a structured summary including, as applicable: background; objectives; data sources; study eligibility criteria, participants, and interventions; study appraisal and synthesis methods; results; limitations; conclusions and implications of key findings; systematic review registration number.

page 1

Rationale

3

Describe the rationale for the review in the context of what is already known.

1st through 4th paragraphs of introduction

Objectives

4

Provide an explicit statement of questions being addressed with reference to participants, interventions, comparisons, outcomes, and study design (PICOS).

4th paragraph of introduction

Protocol and registration

5

Indicate if a review protocol exists, if and where it can be accessed (e.g., Web address), and, if available, provide registration information including registration number.

abstract

Eligibility criteria

6

Specify study characteristics (e.g., PICOS, length of follow-‐up) and report characteristics (e.g., years considered, language, publication status) used as criteria for eligibility, giving rationale.

1st paragraph of selection criteria under methods

Information sources

7

Describe all information sources (e.g., databases with dates of coverage, contact with study authors to identify additional studies) in the search and date last searched.

1st paragraph in search methods under methods

Search

8

Present full electronic search strategy for at least one database, including any limits used, such that it could be repeated.

Supplemental Text 1-5

Study selection

9

State the process for selecting studies (i.e., screening, eligibility, included in systematic review, and, if applicable, included in the meta-‐analysis).

1st paragraph in search methods under methods

Section/topic TITLE Title

ABSTRACT Structured summary

INTRODUCTION

METHODS

PRISMA 2009 Checklist Data collection process

10

Describe method of data extraction from reports (e.g., piloted forms, independently, in duplicate) and any processes for obtaining and confirming data from investigators.

All paragraphs in variable definitions and coding under methods

Data items

11

List and define all variables for which data were sought (e.g., PICOS, funding sources) and any assumptions and simplifications made.

All paragraphs in variable definitions and coding under methods; variables are italicized

Risk of bias in individual studies

12

Describe methods used for assessing risk of bias of individual studies (including specification of whether this was done at the study or outcome level), and how this information is to be used in any data synthesis.

3rd paragraph of variables definitions and coding under methods

Summary measures

13

State the principal summary measures (e.g., risk ratio, difference in means).

4th paragraph of variable definitions and coding under methods

Synthesis of results

14

Describe the methods of handling data and combining results of studies, if done, including measures of 2 consistency (e.g., I ) for each meta-‐analysis.

4th paragraph of variable definitions and coding under methods

Section/topic Risk of bias across studies

# 15

Checklist item Specify any assessment of risk of bias that may affect the cumulative evidence (e.g., publication bias, selective reporting within studies).

Reported on page #

3rd paragraph of variables definitions and coding under

PRISMA 2009 Checklist methods 16

Describe methods of additional analyses (e.g., sensitivity or subgroup analyses, meta-regression), if done, indicating which were pre-‐specified.

Both paragraphs in Harvest Plot under Methods

Study selection

17

Give numbers of studies screened, assessed for eligibility, and included in the review, with reasons for exclusions at each stage, ideally with a flow diagram.

Paragraph in search results under Results

Study characteristics

18

For each study, present characteristics for which data were extracted (e.g., study size, PICOS, follow-up period) and provide the citations.

Can be found in participant characteristics, intervention characteristics, research characteristics, and in Tables 1-8

Risk of bias within studies

19

Present data on risk of bias of each study and, if available, any outcome level assessment (see item 12).

2nd paragraph in research characteristics under Results and Figures 2 and S1

Results of individual studies

20

For all outcomes considered (benefits or harms), present, for each study: (a) simple summary data for each intervention group (b) effect estimates and confidence intervals, ideally with a forest plot.

Tables 2-4

Synthesis of results

21

Present the main results of the review. If meta-analyses are done, include for each, confidence intervals and measures of consistency.

Figures 3-7

Risk of bias across studies

22

Present results of any assessment of risk of bias across studies (see Item 15).

2nd paragraph in research characteristics under Results and Figures 2 and S1

Additional analyses

RESULTS

PRISMA 2009 Checklist 23

Give results of additional analyses, if done (e.g., sensitivity or subgroup analyses, meta-regression [see Item 16]).

Figures 3-7

Summary of evidence

24

Summarize the main findings including the strength of evidence for each main outcome; consider their relevance to key groups (e.g., healthcare providers, users, and policy makers).

Summary of main findings paragraph under discussion

Limitations

25

Discuss limitations at study and outcome level (e.g., risk of bias), and at review-level (e.g., incomplete retrieval of identified research, reporting bias).

Limitations paragraph under discussion

Conclusions

26

Provide a general interpretation of the results in the context of other evidence, and implications for future research.

Conclusions paragraph under discussion

27

Describe sources of funding for the systematic review and other support (e.g., supply of data); role of funders for the systematic review.

page 1

Additional analysis

DISCUSSION

FUNDING Funding

From: Moher D, Liberati A, Tetzlaff J, Altman DG, The PRISMA Group (2009). Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement. PLoS Med 6(6): e1000097. doi:10.1371/journal.pmed1000097

For more information, visit: www.prisma-‐statement.org.

Table S1. Outcome Measures and Outcome Categories for Included Studies Study

Outcome Measures and Outcome Category Behavior Analytic Techniques

Cohen 2006 [60]

Standardized IQ tests [38,42], Reynell Developmental Language Scales-3rd Ed. [48] (developmental, a), Vineland Adaptive Behavior Scales [59] (daily skills, b)

Dawson 2010 [61,71]

Mullen Scales of Early Learning [37] (developmental, a), Vineland Adaptive Behavior Scales [59] (daily skills, b), Repetitive behavior scale [122] (behavior, c)

Eikeseth 2007 [62,72]

Standardized IQ tests [38,45,130] (developmental, a), Vineland Adaptive Behavior Scales [59] (daily skills, b), Child Behavior Checklist [125] (behavior, c)

Eikeseth 2012 [63]

Vineland Adaptive Behavior Scales [59] (daily skills)

Howard 2005 [64]

Standardized IQ tests [38,40-47], Standardized language tests [48-56] (developmental, a), Standardized adaptive behavior scales [40,59,137,138] (daily skills, b)

Jocelyn 1998 [65]

Early Intervention Developmental Profile [126] (developmental, a), Autism Behavior Checklist [127] (behavior, b), Stress-Arousal Checklist [129], Family Assessment Measure [128] (family, c)

Kaale 2012 [66]

Early Social Communication Scale [57] (developmental)


Bayley Scales of Infant Development [38] (developmental, a), Vineland Adaptive Behavior Scales [59] (daily skills, b), Child Behavior Checklist [125] (behavior, c)

Reed 2007 [68]

British Ability Scale-II [131], Psychoeducational Profile-Revised [44] (developmental, a), Vineland Adaptive Behavior Scales [59] (daily skills, b)


Standardized IQ tests [38,41], Standardized language tests [48,57] (developmental, a), Vineland Adaptive Behavior Scales [59] (daily skills, b), Developmental Behavior Checklist [132,133] (behavior, c), Hospital Anxiety and Depression Scale [134], Questionnaire on Resources and StressFriedrich Short Form [135] Kansas Inventory of Parental Perceptions [136] (family, d)

Smith 2000 [70]

Standardized IQ tests [41,42,123], Reynell Developmental Language Scales-3rd Ed. [48] (developmental, a), Vineland Adaptive Behavior Scales [59] (daily skills, b), Child Behavior Checklist [125] (behavior, c), Family Satisfaction Questionnaire [124] (family, d) Cognitive Rehabilitation, Training, and Support

Allor 2010 [75,84]

Standardized language tests [49,140], (developmental, a), Woodcock Language Proficiency BatteryRevised [143], Comprehensive Test of Phonological Processing [144], Test of Word Reading Efficiency [145] (school performance, b)

Browder 2012 [76,85]

Standardized language tests [49,140], (developmental, a), Nonverbal Literacy Assessment [139], (school performance, b)

Burgoyne 2012 [77]

Standardized language tests [55,56], (developmental, a), York Assessment of Early Reading Battery [141], Action Picture Test [142], (school performance, b)

Elwan 2010 [78] *

Subtests from Kaufman Assessment Battery of Children [146] and McCarthy Scales of Children’s Abilities [147] (developmental)

Goetz 2008 [79]

Letter knowledge, early word recognition, word reading [115,148,149] and non word reading subscales of British Achievement Scales [131] (school performance)

Jespen 2002 [80]

Cognitive Assessment System [152] (developmental, a), Adaptive Behavior Scale [153] (daily skills, b), Woodcock-Johnson-Revised [154] (school performance, c)

Panerai 2009 [81]

Psychoeducational Profile-Revised [44] (developmental, a), Vineland Adaptive Behavior Scales [59] (daily skills, b)

Perez 2008 [82]

Stanford-Binet (4th ed) [41] (developmental, a), mathematics, language, and social science examinations (school performance, b)

Tsang 2007 [83] *

Merrill-Palmer [42], Chinese Psychoeducational Profile-Revised [150] (developmental, a), Hong Kong Based Adaptive Behavior Scales [151] (daily skills, b) Parent Training Interventions


Brunet-Lezine Psychomotor Development Scale [39] (developmental)


MacArthur Communicative Development Inventories [58] (developmental, a), Behavior Screening Questionnaire [172] (behavioral, b) Questionnaire on Resources and Stress [135], Parent Feelings Questionnaire [173] (family, c)

Plant 2007 [88]

Eyberg Child Behavior Inventory, Developmental Behavior Checklist [158] (behavior, a), Parenting Scale [159], Parenting Sense of Competence Scale [160], Depression, Anxiety, and Stress Scales [161], Abbreviated Dyadic Adjustment Scale [162] (family, b)

Roberts 2006 [89]

Developmental Behavior Checklist [133] (behavior, a), Family Observation Schedule-Revised III [163], Parenting Scale [159], Depression, Anxiety, & Stress Scale [161] (family, b)

Russell 1999 [90] *

Parental Attitude Scale Towards Management of Intellectual Disability [164] (family)

Shin 2009 [91] *

Vineland Adaptive Behavior Scales [59] (daily skills)

Shu 2005 [92]

Chinese Health Questionnaire-30 [174], World Health Organization Quality of Life – short form [175] (family)

Varma 1992 [93] *

Multiple intelligence subtests [165-168] (developmental, a), Bhat’s behavior rating scale [169] (behavior, b), Marital adjustment [170], parental attitudes [164], and social burden [171] (family, c)

Wong 2010 [94] *

Symbolic Play Test [155], Ritvo-Freeman Real Life Rating Scale [156] (developmental), Parenting Stress Index Short Form [157] (family)

Text S1. Sample Search Strategy for MEDLINE (1946 to June Week 2 2013), Cumulative Index for Nursing and Allied Health (CINAHL; 1981 to 24 June 2013), and EMBASE (1988 to 24 June 2013) 1. exp child development disorders, pervasive/ 2. exp Intellectual Disability/ 3. rett.tw. 4. autis*.tw. 5. (pervasive development* disorder* or PDD or PDDs).tw. 6. (developmental adj delay*).tw. 7. (developmental adj disorder*).tw. 8. (developmental adj disability).tw. 9. (developmental adj disabilities).tw. 10. (developmental adj differen*).tw. 11. ((down* adj syndrome) or (fragile adj X)).tw. 12. (mental adj retard*).tw. 13. (intellectual adj disorder*).tw. 14. (intellectual adj disability).tw. 15. (intellectual adj disabilities).tw. 16. 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13 or 14 or 15 17. behavior therapy/ 18. exp treatment outcome/ 19. (educat* or train* or program* or therap* or intervention* or treatment*).tw. 20. psychosocial.tw. 21. 17 or 18 or 19 or 20 22. 16 and 21 23. limit 22 to (yr=”1992 –Current” and “all child (0 to 18 years)”) 24. qualitative.mp. 25. 23 not 24 26. exp Epidemiologic Methods/ 27. 25 and 26

Text S2: Search Strategy for PsycINFO (1967 to June Week 3 2013) 1. exp pervasive developmental disorders/ 2. (pervasive development* disorder* or PDD or PDDs).tw. 3. rett.tw. 4. autis*.tw. 5. (mental adj retard*).tw. 6. (intellectual adj disorder*).tw. 7. (intellectual adj disability).tw. 8. (intellectual adj disabilities).tw. 9. (developmental adj disorder*).tw. 10. (developmental adj delay*).tw. 11. (developmental adj disability).tw. 12. (developmental adj disabilities).tw. 13. (developmental adj differen*).tw. 14. ((down* adj syndrome) or (fragile adj X)).tw. 15. 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13 or 14 16. behavior therapy/ 17. exp treatment outcome/ 18. (educat* or train* or program* of therap* or intervention* or treatment*).tw. 19. psychosocial.tw. 20. 16 or 17 or 18 or 19 21. 15 and 20 22. limit 21 to (1800 quantitative study and (100 childhood or 200 adolescence ) and yr=”1992 – Current”)

Text S3. Sample Search Strategies for African Index Medicus, Afro Library (AFROLIB), and Index Medicus for the Western Pacific (WPRIM) 1. autism 2. autistic 3. autism spectrum disorder 4. ASD 5. pervasive developmental disorder 6. PDD 7. intellectual disability 8. developmental disability 9. developmental disorder 10. mental retardation 11. autistique 12. troubles du spectre autistique 13. troubles envahissants du developpement 14. PDD deficience intellectuelle 15. troubles du developpement 16. retard mental 17. 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13 or 14 or 15 or 16

Text S4. Search strategy for Literatura Latino Americana em Ciências da Saúde (LILACS): 1. autism 2. autistic 3. autism spectrum disorder 4. ASD 5. pervasive developmental disorder 6. PDD 7. intellectual disability 8. developmental disability 9. developmental disorder 10. mental retardation 11. autismo 12. autista 13. trastorno del desarrollo 14. discapacidad intelectual 15. discapacidad del desarrollo 16. retraso mental 17. 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10 or 11 or 12 or 13 or 14 or 15 or 16

Text S5. Search strategy for Cochrane Central Register of Controlled Trials (CENTRAL; 24 June 2013) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11.

autis* pervasive development* disorder* PDD intellectual disability intellectual disabilities intellectual disorder* mental retardation developmental disability developmental disabilities developmental disorder* 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9 or 10

limit 11to year 1992 to 2012

Text S6: List of Excluded Studies, with Reason Reasons for exclusion, with reference number from reference list below for each excluded study: 1. Did not meet participant criteria (n = 52). Studies: 1, 4, 8, 26, 32, 34, 38, 40, 41, 46, 53, 58, 60, 61, 66, 70, 71, 73, 92, 97, 103, 107, 110, 111, 112, 121, 125, 128, 129, 137, 142, 143, 146, 147, 149, 150, 157, 168, 170, 171, 172, 174, 177, 178, 180, 183, 184, 192, 193, 194, 195, 199 2. Did not have at least two groups in which at least one group received treatment that was compared to another group who either did not receive treatment or received a different treatment (n = 63). Studies: 5, 6, 7, 10, 11, 12, 13, 16, 18, 20, 21, 22, 27, 31, 33, 35, 48, 49, 52, 56, 57, 59, 65, 72, 78, 82, 84, 86, 87, 88, 89, 93, 94, 98, 100, 101, 102, 105, 108, 109, 113, 114, 117, 122, 123, 127, 136, 139, 140, 141, 148, 153, 158, 161, 162, 165, 173, 176, 181, 182, 185, 187, 188 3. Study was not prospective (n = 14). Studies: 17, 43, 44, 45, 51, 55, 95, 99, 135, 138, 156, 167, 191, 200 4. Treatment was not psychosocial (n = 14). Studies: 24, 37, 39, 62, 64, 74, 75, 77, 83, 85, 104, 120, 154, 166 5. Treatment or parent training was not delivered by a non-specialist (n = 54). Studies: 2, 3, 9, 19, 23, 25, 28, 29, 30, 36, 42, 47, 50, 54, 63, 67, 68, 69, 76, 79, 80, 81, 90, 91, 96, 106, 115, 116, 118, 119, 124, 126, 130, 131, 132, 133, 134, 145, 151, 152, 155, 159, 160, 163, 164, 169, 175, 179, 186, 189, 190, 196, 197, 198 6. Could not locate article (n = 3). Studies: 14, 15, 144

References: 1. Abrahamse ME, Junger M, Chavannes EL, Coelman FJG, Boer F, et al. (2012) Parentchild interaction therapy for preschool children with disruptive behaviour problems in the Netherlands. Child Adol Psychiatry Mental Health 6: 24. 2. Aldred C, Green J, Adams C (2004) A new social communication intervention for children with autism: Pilot randomized controlled treatment study suggesting effectiveness. J Child Psychol Psychiatry 45: 1420-1430. 3. Aldred C, Green J, Emsley R, McConachie H (2012) Mediation of treatment effect in a communication intervention for pre-school children with autism. J Autism Dev Disord 42: 447-454. 4. Alfassi M, Weiss I, Lifshitz H (2009) The efficacy of reciprocal teaching in fostering the reading literacy of students with intellectual disabilities. Eur J Spec Needs Educ 24: 291-305. 5. Anan RM, Warner LJ, McGillivary JE, Chong IM, Hines SJ (2008) Group Intensive Family Training (GIFT) for preschoolers with autism spectrum disorders. Behav Interv 23: 165-180. 6. Aparicio MTS, Balana JM (2003) Social Early Stimulation of Trisomy-21 Babies. Early Child Develop Care 173: 557-561. 7. Bachman JA, Bachman WG, Franzel AS, Marcus MC (1994) Preteaching developmentally delayed preschoolers to aid vision screening. Optom Vis Sci 71: 713-716. 8. Baghdadli A, Brisot-Dubois J, Picot MC, Michelon C (2010) [Comparison of the effect of two prosocial interventions about the evolution of recognition of facial expression abilities and social cognition of children with an Asperger syndrome or high functioning autism] TO: Comparaison de l'effet de deux interventions prosociales sur l'evolution des capacites d'identification des expressions faciales et du raisonnement social d'enfants avec un syndrome d'Asperger ou autisme de haut niveau LA: Fre. Neuropsychiatr Enfance Adol 58: 456-462. 9. Bagner DM, Eyberg SM (2007) Parent-child interaction therapy for discruptive behavior in children with mental retardation: A randomized controlled trial. J Clin Child Adolesc Psychol 36: 418-429. 10. Baharav E, Reiser C (2010) Using telepractice in parent training in early autism. Telemed and E Health 16: 727-731. 11. Baker-Ericzen MJ, Stahmer AC, Burns A (2007) Child Demographics Associated With Outcomes in a Community-Based Pivotal Response Training Program. J Posit Behav Interv 9: 52-60. 12. Baltruschat L, Hasselhorn M, Tarbox J, Dixon DR, Najdowski AC, et al. (2011) Addressing working memory in children with autism through behavioral intervention. Res Autism Spectr Disord 5: 267-276. 13. Baltruschat L, Hasselhorn M, Tarbox J, Dixon DR, Najdowski AC, et al. (2011) Further analysis of the effects of positive reinforcement on working memory in children with autism. Res Autism Spectr Disord 5: 855-863. 14. Banerjee M (2006) Autism & communication-A psycho-bio-social approach. Indian J Comm Psychol 2: 1-15.

15. Banerjee M, Ray P, Panda A (2013) Role of sex education on odd sexual and problem behaviour: A study on adolescents with autism. Indian J of Comm Psychol 9: 120. 16. Basil C, Reyes S (2003) Acquisition of literacy skills by children with severe disability. Child Lang Teach Ther 19: 27-48. 17. Bates PE, Cuvo T, Miner CA, Korabek CA (2001) Simulated and community-based instruction involving persons with mild and moderate mental retardation. Res Dev Disabil 22: 95-115. 18. Baylis P, Snowling MJ (2012) Evaluation of a phonological reading programme for children with Down syndrome. Child Lang Teach Ther 28: 39-56. 19. Begeer S, Gevers C, Clifford P, Verhoeve M, Kat K, et al. (2011) Theory of mind training in children with autism: A randomized controlled trial. J Autism Dev Disord 41: 997-1006. 20. Ben Itzchak E, Zachor DA (2011) Who benefits from early intervention in autism spectrum disorders? Res Autism Spectr Disord 5: 345-350. 21. Ben-Itzchak E, Zachor DA (2007) The effects of intellectual functioning and autism severity on outcome of early behavioral intervention for children with autism. Res Dev Disabil 28: 287-303. 22. Bendixen RM, Elder JH, Donaldson S, Kairalla JA, Valcante G, et al. (2011) Effects of a father-based in-home intervention on perceived stress and family dynamics in parents of children with autism. Am J Occup Ther 65: 679-687. 23. Bilgin S, Gozum S (2009) Reducing burnout in mothers with an intellectually disabled child: an education programme. J Adv Nurs. pp. 2552-2561. 24. Bird EK, Gaskell A, Babineau MD, Macdonald S (2000) Novel word acquisition in children with Down syndrome: does modality make a difference? J Commun Disord 33: 241-265. 25. Brandao Coutinho MT (2004) Supporting the family and parental training. Analise Psicologica 22: 55-64. 26. Bruce M, Collins S, Langdon P, Powlitch S, Reynolds S (2010) Does training improve understanding of core concepts in cognitive behaviour therapy by people with intellectual disabilities? A randomized experiment. Brit J Clin Psychol: 1-13. 27. Carr D, Felce J (2007) Brief report: Increase in production of spoken words in some children with autism after PECS teaching to Phase III. J Autism Dev Disord 37: 780-787. 28. Carter AS, Messinger DS, Stone WL, Celimli S, Nahmias AS, et al. (2011) A randomized controlled trial of Hanen's 'More Than Words' in toddlers with early autism symptoms. J Child Psychol Psychiatry 52: 741-752. 29. Chadwick O, Momcilocic N, Rossiter R, Stumbles E, Taylor E (2001) A randomized trial of brief individual versus group parent training for behaviour problems in children with severe learning disabilities. Behav Cogn Psychother 29: 151-167. 30. Chung KKH, Tam YH (2005) Effects of cognitive-based instruction on mathematical problem solving by learners with mild intellectual disabilities. J Intellect Dev Disabil 30: 207-216.

31. Ciechomski LD, Jackson KL, Tonge B, King NJ, Heyne DA (2001) Intellectual disability and anxiety in children: A group-based parent skills-training intervention. Behav Change 18: 204-212. 32. Conner NW, Fraser MW (2011) Preschool Social–Emotional Skills Training: A Controlled Pilot Test of the Making Choices and Strong Families Programs. Res Soc Work Pract 21: 699-711. 33. Conners F, Rosenquist C, Arnett L, Moore M, Hume L (2008) Improving memory span in children with Down syndrome. J Intellect Disabil Res 52: 244-255. 34. Coughlin M, Sharry J, Fitzpatrick C, Guerin S, Drumm M (2009) A controlled clinical evaluation of the parents plus children's programme: a video-based programme for parents of children aged 6 to 11 with behavioural and developmental problems. Clin Child Psychol Psychiatry 14: 541-558. 35. Cowen PS, Reed DA (2002) Effects of respite care for children with developmental disabilities: evaluation of an intervention for at risk families. Public Health Nurs 19: 272-283. 36. Crites SA, Dunn C (2004) Teaching Social Problem Solving to Individuals with Mental Retardation. Educ Train Dev Disabil 39: 301-309. 37. de la Iglesia J, Buceta M, Campos A (2005) Prose learning in children and adults with Down syndrome: The use of visual and mental image strategies to improve recall. J Intellect Dev Disabil 30: 199-206. 38. Demers J, French DC, Moore D (2000) The preliminary evaluation of a program to help educators address the substance use/prevention needs of special students. J Alcohol Drug Educ 46: 14-26. 39. Dessemontet R, Bless G, Morin D (2012) Effects of inclusion on the academic achievement and adaptive behaviour of children with intellectual disabilities. J Intellect Disabil Res 56: 579-587. 40. Drew A, Baird G, Baron-Cohen A, Cox A, Slonims V, et al. (2002) A pilot randomised control trial of a parent training intervention for pre-school children with autism. Eur Child Adolesc Psychiatry 11: 266-272. 41. Drummond J, Fleming D, McDonald L, Kysela GM (2005) Randomized Controlled Trial of a Family Problem-Solving Intervention. Clin Nurs Res 14: 57-80. 42. Drysdale J, Casey J, Porter-Armstrong A (2008) Effectiveness of training on the community skills of children with intellectual disabilities. Scand J Occup Ther 15: 247-255. 43. Eikeseth S, Hayward D, Gale C, Gitlesen J-P, Eldevik S (2009) Intensity of supervision and outcome for preschool aged children receiving early and intensive behavioral interventions: A preliminary study. Res Autism Spectr Disord 3: 6773. 44. Eldevik S, Eikeseth S, Jahr E, Smith T (2006) Effects of Low-Intensity Behavioral Treatment for Children with Autism and Mental Retardation. J Autism Dev Disord 36: 211-224. 45. Eldevik S, Hastings RP, Jahr E, Hughes J (2012) Outcomes of behavioral intervention for children with autism in mainstream pre-school settings. J Autism Dev Disord 42: 210-220.

46. Elosua MR, Garcia-Madruga JA, Gutierrez F, Luque JL, Garate M (2002) Effects of an intervention in active strategies for text comprehension and recall. Span J Psychol 5: 90-101. 47. Erguner-Tekinalp B, Akkok F (2004) The effects of a coping skills training program on the coping skills, hopelessness, and stress levels of mothers of children with autism. Int J Adv Couns 26: 257-269. 48. Fabio RA, Giannatiempo S, Oliva P, Murdaca AM (2011) The increase of attention in Rett Syndrome: A pre-test/post-test research design. J Dev Phys Disabil 23: 99111. 49. Farber MLZ, Maharaj R (2005) Empowering high-risk families of children with disabilities. Res Soc Work Pract 15: 501-515. 50. Fava L, Strauss K, Valeri G, D'Elia L, Arima S, et al. (2011) The effectiveness of a cross-setting complementary staff- and parent-mediated early intensive behavioral intervention for young children with ASD. Res Autism Spectr Disord 5: 14791492. 51. Feldman MA, Werner SE (2002) Collateral effects of behavioral parent training on families of children with developmental disabilities and behavior disorders. Behav Interv 17:. 75-83. 52. Fennick E, Royle J (2003) Community inclusion for children and youth with developmental disabilities. Focus Autism Other Dev Disabl 18: 20-27. 53. Fernell E, Hedvall A, Westerlund J, Carlsson LH, Eriksson M, et al. (2011) Early intervention in 208 Swedish preschoolers with autism spectrum disorder. A prospective naturalistic study. Res Dev Disabil 32: 2092-2101. 54. Fey ME, Warren SF, Brady N, Finestack LH, Bredin-Oja SL, et al. (2006) Early effects of responsivity education/prelinguistic milieu teaching for children with developmental delays and their parents. J Speech Lang Hear Res 49: 526-547. 55. Flanagan HE, Perry A, Freeman NL (2012) Effectiveness of large-scale communitybased intensive Behavioral Intervention: A waitlist comparison study exploring outcomes and predictors. Res Autism Spectr Disord 6: 673-682. 56. Flores MM, Nelson C, Hinton V, Franklin TM, Strozier SD, et al. (2013) Teaching reading comprehension and language skills to students with autism spectrum disorders and developmental disabilities using direct instruction. Educ Train Autism Dev Disabil 48: 41-48. 57. Ganesh Kumar S, Shekhar A, Unnikrishnan B, Kotian MS (2011) Effect of psychosocial intervention on quality of life and disability grading of mentally disabled adolescents. Curr Pediatr Res 15: 127-131. 58. Gaunt L, Moni KB, Jobling A (2012) Developing numeracy in young adults with Down syndrome: A preliminary investigation of specific teaching strategies. J Dev Disabil 18: 10-25. 59. Giarelli E, Souders M, Pinto-Martin J, Bloch J, Levy SE (2005) Intervention pilot for parents of children with autistic spectrum disorder. Pediatr Nurs 31: 389-399. 60. Girolametto L, Weitzman E, Clements-Baartman J (1998) Vocabulary intervention for children with Down syndrome: parent training using focused stimulation. Infant-Toddler Interv 8: 109-125.

61. Godfrey J, Pring T, Gascoigne M (2005) Developing children's conversational skills in mainstream schools: an evaluation of group therapy. Child Lang Teach Ther 21: 251-261. 62. Golnik A, Scal P, Wey A, Gaillard P (2012) Autism-specific primary care medical home intervention. J Autism Dev Disord 42: 1087-1093. 63. Goods KS, Ishijima E, Chang Y-C, Kasari C (2013) Preschool based JASPER intervention in minimally verbal children with autism: Pilot RCT. J Autism Dev Disord 43: 1050-1056. 64. Gordon K, Pasco G, McElduff F, Wade A, Howlin P, et al. (2011) A communicationbased intervention for nonverbal children with autism: What changes? Who benefits? J Consult Clin Psychol 79: 447-457. 65. Gore N, Umizawa H (2011) Challenging behavior training for teaching staff and family carers of children with intellectual disabilities: A preliminary evaluation. J Policy Prac in Intellect Disabil 8: 266-275. 66. Granat T, Nordgren I, Rein G, Sonnander K (2012) Group intervention for siblings of children with disabilities: A pilot study in a clinical setting. Disabil Rehabil 34: 69-75. 67. Green J, Charman T, Mc Conachie H, Aldred C, Slonims V, et al. (2011) Parentmediated communication-focused treatment for preschool children with autism (MRC PACT); a randomised controlled trial. Eur Psychiatry 26: 1897. 68. Green J, Charman T, McConachie H, Aldred C, Slonims V, et al. (2010) Parent-mediated communication-focused treatment in children with autism (PACT): A radomised controlled trial. Lancet 375: 2152-2160. 69. Gulsrud AC, Kasari C, Freeman S, Paparella T (2007) Children with autism's response to novel stimuli while participating in interventions targeting joint attention or symbolic play skills. Autism 11: 535-546. 70. Guralnick MJ, Connor RT, Neville B, Hammond MA (2006) Promoting the PeerRelated Social Development of Young Children With Mild Developmental Delays: Effectiveness of a Comprehensive Intervention. Am J Ment Retard 111: 336-356. 71. Hagiliassis N, Gulbenkoglu H, Di Marco M, Young S, Hudson A (2005) The Anger Management Project: a group intervention for anger in people with physical and multiple disabilities. J Intellect Dev Disabil 30: 86-96. 72. Hagner D, Kurtz A, Cloutier H, Arakelian C, Brucker DL, et al. (2012) Outcomes of a family-centered transition process for students with autism spectrum disorders. Focus Autism Other Dev Disabil 27: 42-50. 73. Holtz CA, Carrasco JM, Mattek RJ, Fox RA (2009) Behavior problems in toddlers with and without developmental delays: comparison of treatment outcomes. Child Fam Behav Ther 31: 292-311. 74. Hong C, Lee I (2012) Effects of neurofeedback training on attention in children with intellectual disability. J Neurother 16: 110-122. 75. Hopkins IM, Gower MW, Perez TA, Smith DS, Amthor FR, et al. (2011) Avatar assistant: Improving social skills in students with an ASD through a computerbased intervention. J Autism Dev Disord 41: 1543-1555. 76. Howlin P, Gordon R, Pasco G, Wade A, Charman T (2007) The effectiveness of Picture Exchange Communication System (PECS) training for teachers of

children with autism: A pragmatic, group randomised controlled trial. J Child Psychol Psychiatry 48: 473-481. 77. Hu J, Lin JD, Yen CF, Loh CH, Hsu SW, et al. (2010) Effectiveness of a stressrelief initiative for primary caregivers of adolescents with intellectual disability. J Intellect Dev Disabil 35: 29-35. 78. Hudson A, Reece J, Cameron C, Matthews J (2009) Effects of child characteristics on the outcomes of a parent support program. J Intellect Dev Disabil 34: 123-132. 79. Hudson AM, Matthews JM, Gavidia-Payne ST, Cameron CA, Mildon RL, et al. (2003) Evaluation of an intervention system for parents of children with intellectual disability and challenging behaviour. J Intellect Disabil Res 47(pt 4/5): 238-249. 80. Ingersoll B (2010) Brief report: Pilot randomized controlled trial of reciprocal imitation training for teaching elicited and spontaneous imitation to children with autism. J Autism Dev Disord 40: 1154-1160. 81. Ingersoll B (2012) Effect of a focused imitation intervention on social functioning in children with autism. J Autism Dev Disord 42: 1768-1773. 82. Itzchak EB, Zachor DA (2009) Change in autism classification with early intervention: Predictors and outcomes. Res Autism Spectr Disord 3: 967-976. 83. Jarusiewicz B (2002) Efficacy of Neurofeedback for Children in the Autistic Spectrum: A Pilot Study. J Neurother 6: 39-49. 84. Jones EA, Carr EG, Feeley KM (2006) Multiple Effects of Joint Attention Intervention for Children With Autism. Behav Modif 30: 782-834. 85. Josman N, Ben-Chaim HM, Friedrich S, Weiss PL (2008) Effectiveness of virtual reality for teaching street-crossing skills to children and adolescents with autism. Int J Disabil Hum Dev 7: 49-56. 86. Kaiser AP, Roberts MY (2013) Parent-implemented enhanced milieu teaching with preschool children who have intellectual disabilities. J Speech Lang Hear Res 56: 295-309. 87. Kalyva E, Avramidis E (2005) Improving Communication Between Children with Autism and Their Peers Through the 'Circle of Friends': A Small-scale Intervention Study. J Appl Res Intellect Disabil 18: 253-261. 88. Kamps DM, Dugan EP, Leonard BR, Daoust PM (1994) Enhanced small group instruction using choral responding and student interaction for children with autism and developmental disabilities. Am J Ment Retard 99: 60-73. 89. Kamps DM, Leonard BR, Vernon S, Dugan EP, Delquadri JC, et al. (1992) Teaching social skills to students with autism to increase peer interactions in an integrated first-grade classroom. J Appl Behav Anal 25: 281-288. 90. Kasari C, Freeman S, Paparella T (2006) Joint attention and symbolic play in young chidlren with autism: A randomized controlled intervention study. J Child Psychol Psychiatry 47: 611-620. 91. Kasari C, Gulsrud AC, Wong C, Kwon S, Locke J (2010) Randomized controlled caregiver mediated joint engagement intervention for toddlers with autism. J Autism Dev Disord 40: 1045-1056. 92. Kasari C, Rotheram-Fuller E, Locke J, Gulsrud A (2012) Making the connection: Randomized controlled trial of social skills at school for children with autism spectrum disorders. J Child Psychol Psychiatry 53: 431-439.

93. Keen D, Couzens D, Muspratt S, Rodger S (2010) The effects of a parent-focused intervention for children with a recent diagnosis of autism spectrum disorder on parenting stress and competence. Res Autism Spectr Disord 4: 229-241. 94. Keen D, Rodger S, Doussin K, Braithwaite M (2007) A pilot study of the effects of a social-pragmatic intervention on the communication and symbolic play of children with autism. Autism 11: 63-71. 95. Kemp C (2003) Investigating the Transition of Young Children With Intellectual Disabilities to Mainstream Classes: An Australian Perspective. Int J Disabil Dev Educ 50: 403-433. 96. Kim JM, Mahoney G (2005) The effects of relationship focused intervention on Korean parents and their young children with disabilities. Res Dev Disabil 26: 117-130. 97. Kirkham MA (1993) Two-year follow-up of skills training with mothers of children with disabilities. Am J Ment Retard 97: 509-520. 98. Kleefman M, Jansen DEMC, Reijneveld SA (2011) The effectiveness of Stepping Stones Triple P: the design of a randomised controlled trial on a parenting programme regarding children with mild intellectual disability and psychosocial problems versus care as usual. BMC Public Health 11: 676. 99. Kleve L, Crimlisk S, Shoebridge P, Greenwood R, Baker B, et al. (2011) Is the Incredible Years programme effective for children with neuro-developmental disorders and for families with Social Services involvement in the "real world" of community CAMHS? Clini Child Psychol Psychiatry 16: 253-264. 100. Klintwall L, Gillberg C, Bolte S, Fernell E (2012) The efficacy of intensive behavioral intervention for children with autism: A matter of allegiance? J Autism Dev Disord 42: 139-140. 101. Kobak KA, Stone WL, Wallace E, Warren Z, Swanson A, et al. (2011) A Webbased tutorial for parents of young children with autism: Results from a pilot study. Telemed E Health 17: 804-808. 102. Konstantareas M, Rios A, Ramnarace C (2010) Intensive Behavioural Intervention (IBI) training: Cooperation and its relationship to language and social competence in children with Autism Spectrum Disorder (ASD). J Dev Disabil 16: 67-68. 103. Kroeger K, Schultz JR, Newsom C (2007) A comparison of two group-delivered social skills programs for young children with autism. J Autism Dev Disord 37: 808-817. 104. Kroesbergen EH, Van Luit JE (2005) Constructivist mathematics education for students with mild mental retardation. Eur J Spec Needs Educ 20: 107-116. 105. Kurani D, Nerurkar A, Miranda L, Jawadwala F, Prabhulkar D (2009) Impact of parents' involvement and engagement in a learning readiness programme for children with severe and profound intellectual disability and complex needs in India. J Intellect Disabil 13: 269-289. 106. Landa RJ, Holman KC, O'Neill AH, Stuart EA (2011) Intervention targeting development of socially synchronous engagement in toddlers with autism spectrum disorder: A randomized controlled trial. J Child Psychol Psychiatry 52: 13-21.

107. Lawton K, Kasari C (2012) Brief report: Longitudinal improvements in the quality of joint attention in preschool children with autism. J Autism Dev Disord 42: 307312. 108. Lecas J-F, Mazaud A-M, Reibel E, Rey A (2011) Using visual strategies to support verbal comprehension in an adolescent with Down syndrome. Child Lang Teach Ther 27: 84-96. 109. Lemons CJ, Fuchs D (2010) Modeling response to reading intervention in children with Down syndrome: An examination of predictors of differential growth. Read Res Q 45: 134-168. 110. Leung C, Fan A, Sanders MR (2013) The effectiveness of a Group Triple P with Chinese parents who have a child with developmental disabilities: A randomized controlled trial. Res Dev Disabil 34: 976-984. 111. Lobato DJ, Kao BT (2005) Brief report: Family-based group intervention for young siblings of children with chronic illness and developmental disability. J Pediatr Psychol 30: 678-682. 112. Loumidis KS, Hill A (1997) Training social problem-solving skill to reduce maladaptive behaviours in intellectual disability groups: the influence of individual difference factors. J Appl Res Intellect Disabil 10: 217-237. 113. Lucas P, Liabo K, Roberts H (2002) Do behavioural treatments for sleep disorders in children with Down's syndrome work? Arch Dis Child 87: 413-414. 114. Lundberg I, Reichenberg M (2013) Developing reading comprehension among students with mild intellectual disabilities: An intervention study. Scan J Educ Res 57: 89-100. 115. Magiati I, Charman T, Howlin P (2007) A two-year prospective follow-up study of community-based early intensive behavioural intervention and specialist nursery provision for children with autism spectrum disorders. J Child Psychol Psychiatry 48: 803-812. 116. Magiati I, Moss J, Charman T, Howlin P (2011) Patterns of change in children with autism spectrum disorders who received community based comprehensive interventions in their pre-school years: A seven year follow-up study. Res Autism Spectr Disord 5: 1016-1027. 117. May FS, McLean LA, Anderson A, Hudson A, Cameron C, et al. (2013) Father participation with mothers in the Signposts program: an initial investigation. J Intellect Dev Disabil 38: 39-47. 118. McConkey R, Truesdale-Kennedy M, Crawford H, McGreevy E, Reavey M, et al. (2010) Preschoolers with autism spectrum disorders: Evaluating the impact of a home-based intervention to promote their communication. Early Child Dev Care 180: 299-315. 119. McIntyre LL (2008) Parent training for young children with developmental disabilities: Randomized controlled trial. Am J Ment Retard 113: 356-368. 120. Montgomery P, Stores G, Wiggs L (2004) The relative efficacy of two brief treatments for sleep problems in young learning disabled (mentally retarded) children: a randomised controlled trial. Arch Dis Child 89: 125-130. 121. Motsch H-J, Ulrich T (2012) Effects of the strategy therapy ‘lexicon pirate’ on lexical deficits in preschool age: A randomized controlled trial. Child Lang Teach Ther 28: 159-175.

122. Mullins LL, Aniol K, Boyd ML, Page MC, Chaney JM (2002) The influence of respite care on psychological distress in parents of children with developmental disabilities: a longitudinal study. Child Serv Soc Pol Res Prac 5: 123-138. 123. Narramore N (2008) Meeting the emotional needs of parents who have a child with complex needs. J Child Young People Nurse 2: 103-107. 124. Nixon CD, Singer GH (1993) Group cognitive-behavioral treatment for excessive parental self-blame and guilt. Am J Ment Retard 97: 665-672. 125. Noone SJ, Hastings RP (2009) Building psychological resilience in support staff caring for people with intellectual disabilities: pilot evaluation of an acceptancebased intervention. J Intellect Dis 13: 43-53. 126. O'Connor C, Stagnitti K (2011) Play, behaviour, language and social skills: The comparison of a play and a non-play intervention within a specialist school setting. Res Dev Disabil 32: 1205-1211. 127. Okuno H, Nagai T, Sakai S, Mohri I, Yamamoto T, et al. (2011) Effectiveness of modified parent training for mothers of children with Pervasive Developmental Disorder on parental confidence and children's behavior. Brain Dev 33: 152-160. 128. Olivar-Parra J-S, De-La-Iglesia-Gutierrez M, Forns M (2011) Training referential communicative skills to individuals with autism spectrum disorder: a pilot study. Psychol Rep 109: 921-939. 129. Oliver PC, Piachaud J, Tyrer P, Regan A, Dack M, et al. (2005) Randomized controlled trial of assertive community treatment in intellectual disability: the TACTILD study. J Intellect Disabil Res 49: 507-515. 130. Oosterling I, Visser J, Swinkels S, Rommelse N, Donders R, et al. (2010) Randomized controlled trial of the focus parent training for toddlers with autism: 1-year outcome. J Autism Dev Disord 40: 1447-1458. 131. Ozonoff S, Miller J (1995) Teaching theory of mind: A new approach to social skills training for individuals with autism. J Autism Dev Disord 25: 415-433. 132. Pajareya K, Nopmaneejumruslers K (2011) A pilot randomized controlled trial of DIR/FloortimeTM parent training intervention for pre-school children with autistic spectrum disorders. Autism 15: 563-577. 133. Palmer SB, Wehmeyer ML, Gipson K, Agran M (2004) Promoting Access to the General Curriculum by Teaching Self-Determination Skills. Except Child 70: 427-439. 134. Panerai S, Ferrante L, Zingale M (2002) Benefits of the Treatment and Education of Austistic and Comunication Handicapped Children (TEACCH) programme as compared with a non-specific approach. J Intellect Disabil Res 46: 318-327. 135. Pelchat D, Bisson J, Ricard N, Perreault M, Bouchard JM (1999) Longitudinal effects of an early family intervention programme on the adaptation of parents of children with a disability. Int J Nurs Stud 36: 465-477. 136. Pelchat D, Ricard N, Lefebvre H (2001) [Parents' adaptation to a delayed developmental child. Effects of a family early intervention program]. Infirm Que 9: 14-24. 137. Perez LM, Garcia EG (2002) Programme for the improvement of metamemory in people with medium and mild mental retardation. Psychol in Spain 6: 96-101.

138. Perry A, Condillac RA (2010) The TRE-ADD preschool parent training program: Program evaluation of an innovative service delivery model. J Dev Disabil 16: 816. 139. Perry A, Cummings A, Geier JD, Freeman NL, Hughes S, et al. (2008) Effectiveness of Intensive Behavioral Intervention in a large, community-based program. Res Autism Spectr Disord 2: 621-642. 140. Perry A, Cummings A, Geier JD, Freeman NL, Hughes S, et al. (2011) Predictors of outcome for children receiving intensive behavioral intervention in a large, community-based program. Res Autism Spectr Disord 5: 592-603. 141. Piazza CC, Fisher WW, Sherer M (1997) Treatment of multiple sleep problems in children with developmental disabilities: faded bedtime with response cost versus bedtime scheduling. Dev Med Child Neurol 39: 414-418. 142. Pillay M, Alderson-Day B, Wright B, Williams C, Urwin B (2011) Autism Spectrum Conditions-Enhancing Nurture and Development (ASCEND): An evaluation of intervention support groups for parents. Clin Child Psychol Psychiatry 16: 5-20. 143. Pineda J, Brang D, Hecht E, Edwards L, Carey S, et al. (2008) Positive behavioral and electrophysiological changes following neurofeedback training in children with autism. Res Autism Spectr Disord 2: 557-581. 144. Puttahraksa P, Tilokskulchai F, Sitthimongkol Y, Prasopkittikul T, Liknapichitkul D (2006) Empowerment program on promoting perceived self-efficacy in caregivers of autistic children. Thai J Nurse Res 10: 180-190. 145. Quinn M, Carr A, Carroll, O'Sullivan D (2007) Parents Plus program 1: evaluation of its effectiveness for pre-school children with developmental disabilities and behavioural problems. J Appl Res Intellect Disabil. pp. 345-359. 146. Quirmbach LM, Lincoln AJ, Feinberg-Gizzo MJ, Ingersoll BR, Andrews SM (2009) Social stories: mechanisms of effectiveness in increasing game play skills in children diagnosed with autism spectrum disorder using a pretest posttest repeated measures randomized control group design. J Autism Dev Disord 39: 299-321. 147. Raghavan R, Newell R, Waseem F, Small N (2009) A randomized controlled trial of a specialist liaison worker model for young people with intellectual disabilities with challenging behaviour and mental health needs. J Appl Res Intellect Disabil 22: 256-263. 148. Reed P, Osborne LA, Corness M (2010) Effectiveness of special nursery provision for children with autism spectrum disorders. Autism 14: 67-82. 149. Reed P, Osborne LA, Makrygianni M, Waddington E, Etherington A, et al. (2013) Evaluation of the Barnet Early Autism Model (BEAM) teaching intervention programme in a 'real world' setting. Res Autism Spect Disord 7: 631-638. 150. Reid MJ, Webster-Stratton C, Hammond M (2007) Enhancing a classroom social competence and problem-solving curriculum by offering parent training to families of moderate- to high-risk elementary school children. J Clin Child Psychol 36: 605-620. 151. Rickards A, Walstab J, Wright-Rossi R, Simpson J, Reddihough D (2009) One-year follow-up of the outcome of a randomized controlled trial of a home-based intervention programme for children with autism and developmental delay and their families. Child Health Care Dev 35: 593-602.

152. Rickards AL, Walstab JE, Wright-Rossi RA, Simpson J, Reddihough DS (2007) A randomized, controlled trial of a home-based intervention program for children with autism and developmental delay. J Dev Behav Pediatr 28: 308-316. 153. Rocha ML, Schreibman L, Stahmer AC (2007) Effectiveness of training parents to teach joint attention in children with autism. J of Early Interv 29: 154-172. 154. Roeyers H (1996) The influence of nonhandicapped peers on the social interactions of children with a pervasive development disorder. J Autism Dev Disord 26: 303320. 155. Rogers SJ, Estes A, Lord C, Vismara L, Winter J, et al. (2012) Effects of a brief Early Start Denver model (ESDM)-based parent intervention on toddlers at risk for autism spectrum disorders: a randomized controlled trial. J Am Acad Child Adolesc Psychiatry 51: 1052-1065. 156. Russell PSS, John JK, Lakshmanan J, Russell S, Lakshmidevi KM (2004) Family intervention and acquisition of adaptive behaviour among intellectually disabled children. J Intellect Disabil 8: 383-395. 157. Ryan C, Charragain CN (2010) Teaching emotion recognition skills to children with autism. J Autism Dev Disord 40: 1505-1511. 158. Sallows GO, Graupner TD (2005) Intensive behavioral treatment for children with autism: Four-year outcome and predictors. Am J Ment Retard 110: 417-438. 159. Salt J, Shemilt J, Sellars V, Boyd S, Coulson T, et al. (2002) The Scottish Centre for Autism preschool treatment programme. Autism 6: 33-46. 160. Samadi SA, McConkey R, Kelly G (2013) Enhancing parental well-being and coping through a family-centred short course for Iranian parents of children with an autism spectrum disorder. Autism 17: 27-43. 161. Sanz MT, Menendez J (2010) Parents' training: Effects of the self-help skills programme with down's syndrome babies. Early Child Dev Care 180: 735-742. 162. Saravanan C, Rangaswamy K (2012) Effectiveness of counselling on the attitudes of mothers towards their children with intellectual disability. Asia Pac J Counsel Psychother 3: 82-94. 163. Schertz HH, Odom SL, Baggett KM, Sideris JH (2013) Effects of Joint Attention Mediated Learning for toddlers with autism spectrum disorders: An initial randomized controlled study. Early Child Res Q 28: 249-258. 164. Schultz Cynthia L, Schultz Noel C, Bruce Elizabeth J, Smyrnios Kosmas X, et al. (1993) Psychoeducational support for parents of children with intellectual disability: An outcome study. Int J Disabil Dev Educ 40: 205-216. 165. Schwartz IS, Sandall SR, McBride BJ, Boulware G-L (2004) Project DATA (Developmentally Appropriate Treatment for Autism): An Inclusive SchoolBased Approach to Educating Young Children with Autism. Topics Early Child Spec Educ 24: 156-168. 166. Self T, Scudder RR, Weheba G, Crumrine D (2007) A virtual approach to teaching safety skills to children with autism spectrum disorder. Topics Lang Disord 27: 242. 167. Sheinkopf SJ, Siegel B (1998) Home-based behavioral treatment of young children with autism. J Autism Dev Disord 28: 15-23.

168. Shu BC, Lung FW, Huang C (2002) Mental health of primary family caregivers with children with intellectual disability who receive a home care programme. J Intellect Disabil Res 46: 257-263. 169. Siller M, Hutman T, Sigman M (2013) A parent-mediated intervention to increase responsive parental behaviors and child communication in children with ASD: A randomized clinical trial. J Autism Dev Disord 43: 540-555. 170. Sofronoff K, Farbotko M (2002) The effectiveness of parent management training to increase self-efficacy in parents of children with Asperger syndrome. Autism 6: 271-286. 171. Sofronoff K, Jahnel D, Sanders M (2011) Stepping Stones Triple P seminars for parents of a child with a disability: a randomized controlled trial. Res Dev Disabil 32: 2253-2262. 172. Sofronoff K, Leslie A, Brown W (2004) Parent management training and Asperger syndrome: a randomized controlled trial to evaluate a parent based intervention. Autism 8: 301-317. 173. Solomon R, Necheles J, Ferch C, Bruckman D (2007) Pilot study of a parent training program for young children with autism: The PLAY Project Home Consultation program. Autism 11: 205-224. 174. Stichter JP, O'Connor KV, Herzog MJ, Lierheimer K, McGhee SD (2012) Social competence intervention for elementary students with Aspergers syndrome and high functioning autism. J Autism Dev Disord 42: 354-366. 175. Stores R, Stores G (2004) Evaluation of Brief Group-Administered Instruction for Parents to Prevent or Minimize Sleep Problems in Young Children with Down Syndrome. J Appl Res Intellect Disabil 17: 61-70. 176. Strain PS, Bovey EH, II (2011) Randomized, controlled trial of the LEAP model of early intervention for young children with autism spectrum disorders. Topics Early Child Spec Educ 31: 133-154. 177. Strauss K, Vicari S, Valeri G, D'Elia L, Arima S, et al. (2012) Parent inclusion in early intensive behavioral intervention: The influence of parental stress, parent treatment fidelity and parent-mediated generalization of behavior targets on child outcomes. Res Dev Disabil 33: 688-703. 178. Tang M-H, Lin C-K, Lin W-H, Chen C-H, Tsai S-W, et al. (2011) The effect of adding a home program to weekly institutional-based therapy for children with undefined developmental delay: a pilot randomized clinical trial. J Chin Med Assoc 74: 259-266. 179. Tannock R, Girolametto L, Siegel LS (1992) Language intervention with children who have developmental delays: effects of an interactive approach. Am J Ment Retard 97: 145-160. 180. Taylor JL, Novaco RW, Gillmer BT, Robertson A, Thorne I (2005) Individual cognitive-behavioural anger treatment for people with mild-borderline intellectual disabilities and histories of aggression: a controlled trial. Brit J Clin Psychol 44: 367-382. 181. Temple K (2007) A randomized comparison of the effect of two prelinguistic communication interventions on the acquisition of spoken communication in preschoolers with ASD. Child Care Health Dev 33: 348-349.

182. Todd S, Bromley J, Ioannou K, Harrison J, Mellor C, et al. (2010) Using GroupBased Parent Training Interventions with Parents of Children with Disabilities: A Description of Process, Content and Outcomes in Clinical Practice. Child Adol Ment Health 15: 171-175. 183. Tonge B, Brereton A, Kiomall M, Mackinnon A, King N, et al. (2006) Effects on parental mental health of an education and skills training program for parents of young children with autism: a randomized controlled trial. J Am Acad Child Adolesc Psychiatry 45: 561-569. 184. van Bysterveldt AK, Gillon GT, Moran C (2006) Enhancing Phonological Awareness and Letter Knowledge in Preschool Children with Down Syndrome. Int J Disabil Dev Educ 53: 301-329. 185. Van Der Bijl C, Alant E, Lloyd L (2006) A comparison of two strategies of sight word instruction in children with mental disability. Res Dev Disabil 27: 43-55. 186. Venker CE, McDuffie A, Weismer SE, Abbeduto L (2012) Increasing verbal responsiveness in parents of children with autism:A pilot study. Autism 16: 568585. 187. Vismara LA, Colombi C, Rogers SJ (2009) Can one hour per week of therapy lead to lasting changes in young children with autism? Autism 13: 93-115. 188. Vismara LA, Rogers SJ (2008) The Early Start Denver Model: a case study of an innovative practice. J Early Interv 31: 91-108. 189. Wang P (2008) Effects of a parent training program on the interactive skills of parents of children with autism in China. J Pol Prac Intellect Disabil 5: 96-104. 190. Warren SF, Fey ME, Finestack LH, Brady NC, Bredin-Oja SL, et al. (2008) A randomized trial of longitudinal effects of low-intensity responsivity education/prelinguistic milieu teaching. J Speech Lang Hear Res 51: 451-470. 191. Wetherby AM, Woods JJ (2006) Early Social Interaction Project for Children With Autism Spectrum Disorders Beginning in the Second Year of Life: A Preliminary Study. Topics Early Child Spec Educ 26: 67-82. 192. Whittingham K, Sofronoff K, Sheffield J, Sanders MR (2009) Stepping Stones Triple P: An RCT of a parenting program with parents of a child diagnosed with an autism spectrum disorder. J Abnorm Child Psychol 37: 469-480. 193. Wiggs L, Stores G (1999) Behavioural treatment for sleep problems in children with severe learning disabilities and challenging daytime behaviour: effect on daytime behaviour. J Child Psychol Psychiatry 40: 627-635. 194. Wiggs L, Stores G (2001) Behavioural treatment for sleep problems in children with severe intellectual disabilities and daytime challenging behaviour: effect on mothers and fathers. Brit J Health Psychol 6: 257-269. 195. Williams BT, Gray KM, Tonge BJ (2012) Teaching emotion recognition skills to young children with autism: a randomised controlled trial of an emotion training programme. J Child Psychol Psychiatry 53: 1268-1276. 196. Wong FKD, Poon A (2010) Cognitive behavioural group treatment for Chinese parents with children with developmental disabilities in Melbourne, Australia: an efficacy study. Aust N Z J Psychiatry 44: 742-749. 197. Wong SY, Lai AC, Martinson I, Wong TKS (2006) Effects of an education programme on family participation in the rehabilitation of children with developmental disability. J Intellect Disabil 10: 165-189.

198. Yildirim A, Asilar RH, Karakurt P (2013) Effects of a nursing intervention program on the depression and perception of family functioning of mothers with intellectually disabled children. J Clin Nurse 22: 251-261. 199. Zachor DA, Ben-Itzchak E, Rabinovich A-L, Lahat E (2007) Change in autism core symptoms with intervention. Res Autism Spectr Disord 1: 304-317. 200. Zachor DA, Itzchak EB (2010) Treatment approach, autism severity and intervention outcomes in young children. Res Autism Spectr Disord 4: 425-432.