Cross Cultural Adaptation and Psychometric Properties of the Malay Version of the Short Sensory Profile Su Im Ee1 • Siew Yim Loh2 • Karuthan Chinna3 • Mary J. Marret 4
1 Institute of Postgraduate Studies, University of Malaya, Kuala Lumpur, Malaysia 2. Department of Rehabilitation Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia. 3. Department of Social preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 4. Department of Peadiatric, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
*Correspondence Siew Yim Loh, Department of Rehabilitation Medicine, University of Malaya, Kuala Lumpur, Malaysia. Email:
[email protected]
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ABSTRACT Aims: This paper presents the translation, the cultural adaptation and the psychometric properties of the Malay version Short Sensory Profile (SSP-M). Methods: Pre-testing (n=30) of the original English SSP established its applicability for use on Malaysian children aged 3 to 10 years. This was followed by the translation and cross-cultural adaptation of the SSP-M. Two forward and two back-translations were compared and reviewed by a committee of 10 experts who validated the content of the SSP-M, before pilot testing (n=30). The final SSP-M questionnaire was completed by 419 parents of typically developing children aged 3 to 10 years. Results: Cronbach’s alpha of each section of the SSP-M ranged from 0.73 to 0.93 and the intraclass correlation coefficient (ICC) indicated good reliability (0.62 to 0.93). The seven factor model of the SSP-M had an adequate fit with evidence of convergent and discriminant validity. Conclusions: We conclude that the SSP-M is a valid and reliable screening tool for use in Malaysia with Malay-speaking parents of children aged 3 to 10 years. The SSP-M enables Malay-speaking parents to answer the questionnaire with better reliability, and provides occupational therapists with a valid tool to screen for sensory processing difficulties.
KEYWORDS. sensory processing, cross cultural adaptation, psychometric properties, short sensory profile, validity
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Sensory processing (SP) refers to how the central and peripheral nervous systems manage incoming sensory information, including the reception, modulation, integration, and organization of sensory stimuli (Miller et al., 2000). Based on the work of Ayres, Dunn ( 1997; 2001) developed a model of sensory processing. According to Ayres, (1995) senses provide information about the body and surrounding environment to the brain which then organizes and integrates the sensory input. Well organized sensations are believed to contribute towards the formation of
perceptions that facilitate behaviour and learning
Conversely, poor organization and integration of sensation will result in learning difficulties and behavioural problems (Bundy et al., 2002; Schaaf et al., 2010). Sensory processing difficulty refers to a set of impairments where sensory information is not adequately processed with consequent functional difficulties in many aspects of the daily lives of affected individuals. Sensory Processing Difficulty can affect more than one modality of sensation, whether auditory, tactile, taste, olfactory, visual, proprioception or vestibular (Bar-Shalita et al., 2005; Lane, 2002; Schaaf et al., 2010), resulting in detrimental effects on an individual’s participation in daily activities, social interaction and play (Bar-Shalita et al., 2008; Bundy et al., 2001; Dunn, 1997; Engel-Yeger and Ziv-On, 2011; Nadon, 2011; Reynolds et al., 2011; Schaaf et al., 2003) as well as the development of social skills, self-confidence and selfesteem (Parham and Mailloux, 2010). Sensory processing difficulties can ultimately reduce an individual’s quality of life and well-being(Dunn, 2001). Sensory processing difficulties are estimated to affect between 5% to 16% of normal population in studies of children in the USA (Ahn et al., 2004; Ben-Sasson et al., 2009). Studies in the USA and Australia have found that between 69% to 95% of children with Autism Spectrum Disorder (ASD) display symptoms of sensory processing difficulties (Baranek et al., 2006; Leekam et al., 2007; Tomchek and Dunn, 2007; Baker et al., 2008).
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Evidence of sensory processing difficulty has also been found in individuals with ADHD (Ermer and Dunn, 1998), atopic dermatitis (Engel-Yeger et al., 2007), asthma(Engel-Yeger et al., 2014) and selective eating (Farrow and Coulthard, 2012). The measurement of sensory processing difficulty requires an appropriate instrument. There are very few assessment tools that are suitable for use in children. The Short Sensory Profile (SSP;McIntosh et al.,1999) is a useful instrument for assessment of sensory processing difficulties in children that is commonly used by occupational therapists in Malaysia. However without a validated version in Malay, the national language spoken by the majority of Malaysians, its utility is limited. Currently, use of the SSP in Malaysia is confined to a minority of English- speaking parents who would be able to complete the SSP. While individual therapists may attempt their own translation to administer the SSP to non-English speaking parents, the process is time consuming and lacks standardization. The availability of a Malay version of the SSP would allow expansion of its use to benefit the wider Malayspeaking population in Malaysia. In order to have a reliable and valid tool, the methodology used in translation is of utmost importance. To date, the SSP has been translated into Hebrew (Engel-Yeger, 2010) and Spanish. The process of translation and cross cultural adaptation for the Hebrew version is well documented. Production of the Hebrew version involved forward and backward translation, calculation of internal consistency and principle component analysis to test for further psychometric properties of this version (Engel-Yeger, 2010). However details of the translation and cross cultural adaptation process for the Spanish version SSP have not been published. To date, the reliability and validity of this version has not been established (Román-Oyola and Reynolds, 2010) and is limited to a small US study to examine the content validity of the Spanish version(Román-Oyola and Reynolds, 2010) through a cognitive interview with eight Puerto Rican mothers.
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The aims of this study were to translate, culturally adapt and examine the reliability, content validity and construct validity of the Malay version of the Short Sensory Profile (SSPM) for use in Malaysia among Malay- speaking parents of children aged 3 to 10 years. In this study, we conducted a comprehensive translation, cultural adaption and examination of the reliability, content validity and construct validity of the Malay version of the Short Sensory Profile (SSP-M) based on recommended criteria (Beaton et al., 2000; Sousa and Rojjanasrirat, 2011). Prior to translation, applicability of the SSP to the local context was established through a test retest study with the original English version on 30 English speaking Malaysian parents of typically developing children using convenience sampling. The Cronbach’s alpha for each section ranged from 0.62 to 0.89. The Cronbach’s alpha for the total scale was 0.93. The test-retest reliability of individual items determined by the intraclass correlation coefficient (ICC) ranged from 0.70 to 0.93, except for item 30 where the ICC was 0.58. This preliminary study confirmed that the SSP is applicable for use with English- speaking Malaysian parents. METHODS Permission to use and translate the SSP(McIntosh et al., 1999) into Malay was granted from Pearson Company (Pearson, 2013). The study was reviewed and received ethics clearance from the Medical Ethics Committee of the University of Malaya Medical Centre. Permission to recruit the parents of children attending kindergartens and schools was obtained from the Ministry of Education of Malaysia. Parents were recruited via the heads and principals of schools and kindergartens. An initial draft Malay translation was obtained through a process of two forward and two backward translations. Cultural adaptation and content validation of this draft version was carried out through consultation with a panel of experts and participants
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(n= 30) of a pilot test to obtain a final version of the SSP-M. This final version of the SSP-M was tested on 419 parents for construct validity. Short Sensory Profile The Short Sensory Profile (SSP) is a questionnaire used to screen children aged 3 to 10 based on caregiver reports. The 38-item questionnaire is divided into 7 sections: Tactile sensitivity (7
items),
Taste/Smell
Sensitivity
(4
items),
Movement
Sensitivity
(3
items),
Underresponsive/Seeks Sensation (7 items), Auditory Filtering (6 items), Low Energy/weak (6 items), and Visual/Auditory Sensitivity (5 items). The frequencies of engagement in the described behaviours are indicated on a 5-point Likert scale (1=always, 2=frequently, 3=occasionally, 4=seldom and 5=never) (McIntosh et al., 1999). The total score for an individual ranges from 38 to 190. Scores from 155 to 190 are interpreted as “typical performance”.
A score ranging from 38 to 141 is categorised as “definite difference”
indicating the likelihood that the child is having significant problems with processing sensory stimuli and consequent difficulties in performing daily life activities. An intermediate score ranging from 142 and 154 is classified as “probable difference” (Dunn, 1999). According to the developers, internal consistency and internal validity of the total and section scores range from 0.70 to 0.90 and 0.25 to 0.76, respectively. The SSP can be used to screen for a variety of sensory processing difficulties due to the conceptual relationship between sections of SSP and the long SP(McIntosh et al., 1999). Procedure Translation, Cross Cultural Adaptation and Content Validation The process of translation, cross cultural adaptation and validation was conducted in accordance with the American Educational Research Association, the American Psychological Association, and the National Council of Measurement in Education ( AERA et al., 1985) and recognized guidelines (Beaton et al., 2000; Sousa and Rojjanasrirat, 2011) as
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well as requirements stipulated in the NCS Pearson Inc. Research Translation License Agreement. The original version of the SSP was forward translated from English to Malay independently by two bilingual native Malay speakers. Back translation from Malay into English was carried out by two qualified local bilingual translators from non-medical backgrounds who were blind to the original English version of the SSP. The two initial forward translations were merged to form a draft Malay version that was evaluated by a panel of 10 experts for semantic, idiomatic, and conceptual equivalence. This panel consisted of the researcher, four bilingual native speakers of Malay, one language expert; three bilingual occupational therapists and a bilingual pediatrician. Based on recommendations by this expert panel, minor modifications were made to the draft Malay version to produce an amended version, the SSP-M. Proof reading of the SSP-M was done by two persons, a native Malayspeaking occupational therapist and a teacher proficient in Malay (who was also a parent). Through this process, a grammatically correct, easier to read, and culturally acceptable SSPM was developed. A third and final backward translation of the SSP-M into English was conducted by a professional translator and the translation was found to be similar to the original SSP. The forward and backward translation were sent to NCS Pearson(Pearson, 2013) the copyright owner of SSP.
Content Validation by Occupational Therapists This process was carried out by 10 Malaysian occupational therapists proficient in Malay with 3 to 10 years of working experience in the field of pediatrics to further support the conceptual equivalence (clarity) and content validity of the SSP-M. They were asked to rate the instructions, items and the response format of the SSP-M as “clear” or “unclear” and to provide suggestions to improve the clarity of statements that were rated as “unclear”.
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These 10 occupational therapists were also asked to examine the content validity of the SSPM by using a 4 point rating scale (1 = “not relevant” to 4= ”very relevant”) (Davis et al., 1992) and evaluate the relevance of individual items of the SSP-M. An expert panel of 3 to 10 members is recommended by Lynn (1986). Content Validation by Parents of children with Typical Development Following the content validation by the panel of occupational therapists, pilot testing of the SSP-M was conducted on 30 Malay speaking parents of various ethnicities who had typically developing children aged 3 to 10 years old without any medical conditions associated with developmental problems (e.g., attention deficit hyperactivity disorder, Down syndrome, cerebral palsy). Participating parents signed written consent and completed a questionnaire containing questions on demographic data of parents and their children together with the SSPM. Participants were asked to comment on words and sentences that were unclear.
In
addition, the researcher also conducted brief cognitive interviews, where participants were asked about any items that were unclear to them to further verify the content validity of SSPM and to ensure that it would be easily understood. This sample size and interview as a qualitative measure of content validity was based on the recommendation of Beaton et al.(2000). Psychometric Properties of the Malay Version of SSP The same 30 parents who were in the pilot test were recruited for a retest within an interval of one to two weeks. Each parent completed a questionnaire with reference to one child. Construct Validity. In order to test the construct validity of the SSP-M, the questionnaire was administered to a larger sample. The sample size was determined by rule of thumb following the recommendation of at least 10 respondents per item and at least 300 respondents for factor analysis (Tabachnick and Fidell 2007). The criteria for inclusion in this study were (1)
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Respondents were parents of typically developing children aged 3 to 10 years old. (2) Neither the child nor siblings had any medical diagnosis (e.g. attention deficit hyperactivity disorder, Down syndrome, cerebral palsy, autism) or had a health condition associated with delayed development such as low birth weight or prematurity. (3)
Ability to speak read and
understand Malay language. The participants were recruited from parents of children attending 6 kindergartens and 6 primary schools in Selangor and Kuala Lumpur. A written information sheet was provided to ensure that the participants had sufficient information on the conduct of the research. Parents who agreed to participate signed the consent form and then completed a questionnaire containing questions on the demographic profile of the parent and child as well as the SSP-M. Instructions for completion of the questionnaire were provided. The questionnaires were distributed through an appointed teacher by the school management and the researchers during activities in the school or kindergarten that were attended by parents. Data Analysis The minimum inter-rater agreement among the experts for clarity was set at 80% (Topf, 1986). Content validity examines the degree to which samples of items, taken together, constitute an adequate operational definition of a construct being measured (Polit and Beck, 2006). The assessment of content validity by the panel of experts was analysed by calculation of the content validity index (CVI). The CVI, is easy to understand, and can be used as a guide for modification or deletion of instrument items (Polit and Beck, 2006). The CVI was calculated at both item level (I-CVI) and scale level (S-CVI). The I-CVI is computed as the number of experts giving a rating 3 or 4 to the relevance of each item, divided by the total number of experts. The I-CVI which expresses the proportion of agreement on the relevance of each item should be at least 0.78 (Lynn, 1986). The S-CVI is defined as “the proportion of items on an
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instrument that achieved a rating of 3 or 4 by the content experts” (Beck and Gable, 2001; Lynn, 1986) The S-CVI which was calculated using the average calculation method, SCVI/Ave should be ≥ 0.90 (Waltz et al., 2005). Descriptive statistics were obtained using the statistical software SPSS version 21. Means and standard deviations were used to describe continuous variables, and frequencies and percentages were used to describe categorical variables. Internal consistency of the translated SSP-M was examined using Cronbach’s Alpha for each section scale and testretest reliability was examined using the intraclass correlation coefficient (ICC). Confirmatory factor analysis (CFA) was used to determine if the items in the 7 constructs as in the original English SSP were appropriate as well as to improve the instrument, if necessary. CFA was performed using AMOS version 21 software. In this study we examined factor loadings, factor intercorrelations, as well as goodness of fit indices. Four indices for goodness of fit were used in this study, satisfying the recommendation for at least 3 to 4 goodness of fit(GOF) scores (Hair et al., 2010): the ratio between Chi-square and degree of freedom (X2/df) value, with a ratio of 3 indicating good or acceptable fit(Chin and Todd, 1995), the Comparative Fit Index (CFI; Bentler, 1990) and Tucker-Lewis Index (TLI; Tucker and Lewis, 1973) for which values above .90 indicate good fit (Hair et al., 2010) and Root Mean Square Error of approximation (RMSEA; Steiger, 1990), where a value less than .08 is considered acceptable(Marsh et al., 2004). Composite reliability (ω) and average variance extracted values were calculated from factor loadings.
RESULTS Translation, Cross Cultural Adaptation and Content Validity The forward translation process was carried out without much difficulty. However the backward translations of items 14, 21, 32 and 33 were not consistent with the original English
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SSP. These difficulties arose either because there was no word of equivalent meaning in Malay or because of lack of familiarity with words that are rarely used in ordinary communication. As there is no single Malay word that conveys the meaning of “prop” in the phrase “props to support self’ in item 32, words used by both forward translator were combined to construct the phrase “menupang dan menyandar untuk menyokong diri” (use hands and lean to support self”). As the Malay phrase “balik kuang” to translate “somersaults” in item 14 is not commonly used in daily communication, the English word “somersaults” was added to the phrase for better clarity. As the word “bergulung” used to translate “twisted” in item 21 conveyed the idea of “rolling”, the word” untidily” was added in brackets to communicate the equivalent meaning. The translation of the phrase “poor endurance” for item 33 as “kurang daya tahan” lacked conceptual equivalence as it conveyed “lack of immmunity”rather than inadequate stamina. Members of the expert panel agreed to change this to “Kurang ketahanan diri” which means “poor self edurance”. Item 3 posed difficulties with regard to cultural norms. The cited example of children walking barefoot “especially in sand or grass” was regarded to be inappropriate as Malaysian children in urban areas do not usually walk barefoot on sand unless they are at the beach. In addition, most playgrounds in Malaysia do not have sand. To make it culturally appropriate, this phrase was amended as “terutamanya di atas pasir pantai atau rumput” specifying that reference was made to “sand on the beach”. Content Validity Inter-rater agreement among experts for all the items ranged from 90% to 100%, except for item 32(70%). Item 32 was then evaluated and revised. The phrase “menupang dan menyandar untuk menyokong diri”’ “use hand and lean to support self” ” was substituted with “menongkat /menyandar untuk menyokong diri” or “used body part/lean to support self” by consensus among all the experts. The CVI for 38 items ranged from 0.90 to 1.00 and S-
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CVI/Ave of 0.99. In the content related validation by participants for clarity of the SSP-M, no major changes were proposed by the participants with regard to clarity. Psychometric Properties Pilot Test In the pilot study for SSP-M, the Cronbach’s alpha for each section ranged from 0.73 to 0.93 and the total scale was 0.94(refer to Table 1). The item by item test-retest reliability determined by intraclass correlation coefficient (ICC) ranged from 0.62 to 0.93. ICC for the seven sections ranged between 0.84 to 0.96. All items were retained and no modification was needed. Insert Table 1 Participants The purposive sample consisted of 419 typically developing children. The socio-demographic characteristics of the children and their parents are presented in Table 2. The children in the sample were aged between 3 and 10 years old (mean= 7.7, SD 1.7). Insert Table 2 Results from confirmatory factor analyses The Final version of SSP-M was tested for construct validity and goodness of fit indices. Internal consistency was measured by composite reliability which is one component of convergent validity. The tested seven-factor model is shown in Figure 1. After adjusting for correlated error terms, the 7 factor model of SSP-M showed a good fit [The Chi-square/df = 1.94, TLI = 0.91, CFI = 0.92, RMSEA = 0.05]. The model fit indices are provided in Table 3. Insert Figure 1
Insert Table 3
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According to Hair et al. (2010), the correlation between the constructs should not be too high. A correlation value of more than 0.85 indicates a problem of multicollinearity between the constructs. The correlation values between the constructs are provided in Table 4. In this table, the maximum correlation value was 0.73. Insert Table 4
The factor loading, composite reliability (CR) and average variance extracted (AVE) values for each construct are provided in Table 5. All items were statistically significant (p
