Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Martin M, Clare L, Altgassen AM, Cameron MH, Zehnder F
This is a reprint of a Cochrane review, prepared and maintained by The Cochrane Collaboration and published in The Cochrane Library 2011, Issue 1 http://www.thecochranelibrary.com
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
TABLE OF CONTENTS HEADER . . . . . . . . . . . . . . . . . . ABSTRACT . . . . . . . . . . . . . . . . . PLAIN LANGUAGE SUMMARY . . . . . . . . . BACKGROUND . . . . . . . . . . . . . . . OBJECTIVES . . . . . . . . . . . . . . . . METHODS . . . . . . . . . . . . . . . . . RESULTS . . . . . . . . . . . . . . . . . . DISCUSSION . . . . . . . . . . . . . . . . AUTHORS’ CONCLUSIONS . . . . . . . . . . ACKNOWLEDGEMENTS . . . . . . . . . . . REFERENCES . . . . . . . . . . . . . . . . CHARACTERISTICS OF STUDIES . . . . . . . . DATA AND ANALYSES . . . . . . . . . . . . . HISTORY . . . . . . . . . . . . . . . . . . CONTRIBUTIONS OF AUTHORS . . . . . . . . DECLARATIONS OF INTEREST . . . . . . . . . SOURCES OF SUPPORT . . . . . . . . . . . . DIFFERENCES BETWEEN PROTOCOL AND REVIEW INDEX TERMS . . . . . . . . . . . . . . .
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Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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[Intervention Review]
Cognition-based interventions for healthy older people and people with mild cognitive impairment Mike Martin1 , Linda Clare2 , Anne Mareike Altgassen3 , Michelle H Cameron4 , Franzisca Zehnder1 1 Psychologisches Institut, Universität Zürich, Lehrstuhl Gerontopsychologie, Zürich, Switzerland. 2 School of Psychology, University of Wales Bangor, Bangor, UK. 3 University of Dresden, Dresden, Germany. 4 Department of Neurology, Oregon Health and Science University, Portland, Oregon, USA
Contact address: Mike Martin, Psychologisches Institut, Universität Zürich, Lehrstuhl Gerontopsychologie, Binzmühlestrasse 14/24, Zürich, CH-8050, Switzerland.
[email protected]. Editorial group: Cochrane Dementia and Cognitive Improvement Group. Publication status and date: New, published in Issue 1, 2011. Review content assessed as up-to-date: 2 January 2009. Citation: Martin M, Clare L, Altgassen AM, Cameron MH, Zehnder F. Cognition-based interventions for healthy older people and people with mild cognitive impairment. Cochrane Database of Systematic Reviews 2011, Issue 1. Art. No.: CD006220. DOI: 10.1002/14651858.CD006220.pub2. Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
ABSTRACT Background Evidence from some, but not all non-randomised studies suggest the possibility that cognitive training may influence cognitive functioning in older people. Due to the differences among cognitive training interventions reported in the literature, giving a general overview of the current literature remains difficult. Objectives To systematically review the literature and summarize the effect of cognitive training interventions on various domains of cognitive function (ie memory, executive function, attention and speed) in healthy older people and in people with mild cognitive impairment. Search methods The CDCIG Specialized Register was searched on 30 September 2007 for all years up to December 2005. The Cochrane Library, MEDLINE, EMBASE, PsycINFO and CINAHL were searched separately on 30 September 2007 to find trials with healthy people. These results were supplemented by searches from January 1970 to September 2007 in PsychInfo/Psyndex, ISI Web of Knowledge and PubMed. Selection criteria RCTs of interventions evaluating the effectiveness of cognitive training for healthy older people and people with mild cognitive impairment from 1970 to 2007 that met inclusion criteria were selected. Data collection and analysis Authors independently extracted data and assessed trial quality. Meta-analysis was performed when appropriate. Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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Main results Only data on memory training could be pooled for analysis. Within this domain, training interventions were grouped according to several outcome variables. Results showed that for healthy older adults, immediate and delayed verbal recall improved significantly through training compared to a no-treatment control condition. We did not find any specific memory training effects though as the improvements observed did not exceed the improvement in the active control condition. For individuals with mild cognitive impairment, our analyses demonstrate the same pattern. Thus, there is currently little evidence on the effectiveness and specificity of memory interventions for healthy older adults and individuals with mild cognitive impairment. Authors’ conclusions There is evidence that cognitive interventions do lead to performance gains but none of the effects observed could be attributable specifically to cognitive training, as the improvements observed did not exceed the improvement in active control conditions. This does not mean that longer, more intense or different interventions might not be effective, but that those which have been reported thus far have only limited effect. We therefore suggest more standardized study protocols in order to maximize comparability of studies and to maximize the possibility of data pooling - also in other cognitive domains than memory.
PLAIN LANGUAGE SUMMARY Effects of memory training in healthy older adults and older adults with mild cognitive impairment There is an increasing interest in information on the effectiveness of cognitive training interventions to improve memory in normal and mildly cognitively impaired older adults (60 years and older). We analyzed all cognitive interventions between 1970 and 2007 to determine their effectiveness. The results suggest that cognitive interventions do lead to performance improvements and that the size of the effects differs for different kinds of memory skills in healthy older adults and people with mild cognitive impairment. In particular, immediate and delayed verbal recall improved significantly through training compared to a no-treatment control condition but the improvements observed did not exceed the improvement in the active control conditions.
BACKGROUND As our societies age, and at the same time become more technologically complex, there is increasing interest in understanding the effects of ageing on cognitive function. We draw on the range of abilities in areas such as attention, perception, memory, and language for many activities in our daily lives. Most people, although not all, experience a cognitive decline in old age. There is, however, also evidence for potential gains in performance, in particular in domains where performance is supported by greater experience. This can be demonstrated in a number of areas of expertise, ranging from vocabulary to job-specific skills and knowledge. These findings show that there is potential for cognitive plasticity (change and adaptation) in later life (Hoyer 2006; Kliegl 1989; Verhaeghen 1992), whereby performance can be enhanced under optimal conditions (Singer 2003). The possible extent and limits of cognitive plasticity in later life remain to be determined. Understanding more about the processes underlying these changes in cognitive performance may offer various avenues for support-
ing cognitive functioning in later life. Findings from a number of studies have indicated that cognitively-stimulating activity may help to protect against cognitive decline in later life (Wilson 2002). Building on these observations, researchers have attempted to enhance or maintain cognitive functioning in older people by means of systematic cognition-based interventions such as memory training. It is important to establish to what extent cognitive performance can be improved through systematic training across adulthood and old age, and for how long any gains are maintained. It is also important to establish what factors influence the extent of any gains for a given individual, and to determine how different features of the training, such as intensity, frequency, duration, or focus, impact on the size of the gains (Hoyer 2006; Nyberg 2005; Willis 2001). For the majority of older people the extent of any cognitive decline is relatively small, but some individuals develop more extensive difficulties and are at greater risk of developing a form of dementia. Various terms and definitions have been applied to this group; cur-
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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rently, they are likely to be described as experiencing ’mild cognitive impairment’. Individuals with MCI display cognitive changes that are not severe enough to fulfil diagnostic criteria for dementia, but are greater than those typically observed in their age group (Larrieu 2002; Petersen 2001). Earlier definitions emphasize the differentiation from optimal ageing (e.g. “Benign Senescent Forgetfulness”; Kral 1962; “Age-Associated Memory Impairment”; AAMI; Crook 1986), or the identification of preclinical dementia patients (e.g. “Malignant Senescent Forgetfulness”; Kral 1962; “Cognitive Impairment, No Dementia”; CIND; Graham 1997). The term MCI as defined by the American Psychiatric Association (APA 1987) is a condition involving impaired short- and longterm memory, but no functional impairment. MCI is assumed to be a precursor of dementia, i.e. a transitional state between normal cognitive decline in old age and dementia. Due to the variability in definitions, studies investigating prevalence and incidence of MCI come to different conclusions (Kratz 2002). Prevalence rates vary between 5% and 25% (Kumar 2005; Manly 2005; Purser 2005), incidence rates between 0.5 and 8% (Busse 2003; Larrieu 2002; Jungwirth 2005). Older people with mild cognitive impairment constitute a particularly vulnerable, at-risk group. Cognition-based interventions may offer the possibility of maintaining or improving cognitive function, and perhaps prevent or delay progression to dementia (Hultsch 1999; Schooler 2001; Stern 2002; Unverzagt 2007). It is also important to determine whether the possible benefits differ from those seen in healthy older people, and whether the same or different forms of intervention are most suitable (Nyberg 2005).
Intervention This review will assess the effectiveness of cognitive training. Cognitive training is defined as an intervention providing structured practice on tasks relevant to aspects of cognitive functioning, such as memory, attention, language or executive function. Standardized tasks are used (Clare 2003) but level of difficulty may be graded to allow for individual variations in ability. The selected tasks vary in degree of specificity, with some interventions focusing on very specific abilities and strategies, and others taking a more multimodal and holistic approach. Cognitive training may be offered in various forms, including individual or group sessions, and tasks may be presented in various modalities, including pencil-and-paper or computerised versions. There is wide variation in frequency and duration of training sessions. This intervention approach is intended to address cognitive function and/or cognitive impairment directly and to produce improvements in performance on standardised measures of the relevant domains. Effects on performance of specific tasks trained in the intervention may also be considered.
Rationale Numerous studies report the effects of cognition-focused interventions with older people. There is some evidence for cognitive plasticity in later life as well as a possible protective effect of engaging in cognitively-stimulating activity. This suggests there may be potential to improve cognitive functioning in later life through cognitive training interventions, and this in turn might help to support continued independence and maximise quality of life for otherwise healthy older people. For older people who are already experiencing mild cognitive impairment, and who are at increased risk of developing dementia, cognition-focused interventions may help to improve or maintain the level of cognitive performance and thereby delay or prevent further decline (Hoyer 2006; Wilson 2002). The most frequently reported form of cognition-focused intervention is cognitive training. Cognitive training involves individual or group sessions with practice on tasks targeting aspects of cognitive functioning such as memory, attention and language. The precise parameters of cognitive training interventions reported in the literature vary considerably, and as a result it has been difficult to draw firm conclusions about efficacy. This review aims to gain a clearer picture of the effectiveness of cognitive training, in order to provide guidance on when to apply which training to whom and how often in order to achieve the greatest benefits. Effectiveness can be considered in terms of improvements on test scores in the areas of cognitive functioning targeted in the training, maintenance of improvements over time, transfer of training effects to other kinds of cognitive tasks, and generalisation of effects to everyday functioning. It is also important to consider what factors may be responsible for any benefits resulting from cognitive training, and whether the same, or different approaches are needed for healthy older people and older people with mild cognitive impairment. Cognition-based interventions such as memory training have focused on examining the potential for improvement of cognitive functioning in normal ageing and on determining the limits of cognitive plasticity in old age (Hoyer 2006; Kliegl 1989; Verhaeghen 1992). Cognitive plasticity refers to cognitive changes and adaptations, and especially to the possible performance of people under optimal conditions (Singer 2003). Current practice in cognition-based interventions includes group training targeting memory, attention and language. Cognitive training interventions may address individuals or groups. They differ with regards to trained abilities (e.g. memory, attention, speed of information processing), specificity of training (e.g. training of text recall vs. multimodal and holistic approaches training a combination of abilities), strategies practiced in the training sessions (e.g. method of loci, imagery training), duration of training sessions and overall training period, frequency of training sessions, group size and participant characteristics (e.g. education, personality, preferred learning style etc.). Key questions in cognition-based interventions are the range of potential improvements in essential areas of cognitive function-
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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ing, maintenance of improvements, and transfer of training effects to everyday functioning. Understanding the factors responsible for improvements provides the possibility of making cognitive interventions more cost-effective. In addition, differences in effects and optimal training methods between normal older adults and adults with mild cognitive impairments can be examined. Findings might suggest that preventive interventions at earlier ages might be promising, but need to be examined for long-term effects. Due to the differences among cognitive training interventions reported in the literature, giving a general overview of the current literature remains difficult. Moreover, conclusions of studies are based on different designs and outcomes, such as pre-post comparisons, randomized control groups or comparisons with alternative trainings (active controls). The present review aims to gain a clearer picture of the effectiveness of cognitive training, in order to provide guidance on when to apply which training to whom and how often in order to optimize efficacy.
Types of participants • Participants (both male and female) aged 60 years or older • Any setting (group and individual) • Either healthy older people with no diagnosis or older people who meet criteria for mild cognitive impairment; Peterson criteria for MCI were used; depressive symptoms were excluded by administration of GDS or Profile of Mood States. • Normally educated • Participants with a diagnosis of dementia were excluded • Profiles of general cognitive ability and cognitive functioning in relevant domains, as indicated by performance on standardised measures, must be documented to allow an evaluation of participants’ cognitive status and, specifically, whether they fit the definition of mild cognitive impairment. In order not to exclude studies that may be relevant for this review, none of the specific definitions of mild cognitive impairment are particularly included or excluded, but information on participants’ cognitive ability is required for classification of individual cognitive status. We need information on participants’ memory and general cognitive ability in comparison to norms to be able to classify participants on individual cognitive status.
OBJECTIVES The purpose of the present review is to evaluate the effectiveness of cognitive training in healthy older adults and older adults with mild cognitive impairment. Therefore, studies examining cognitive training with the above mentioned target groups are analysed with regards to training effectiveness and (if possible) sustainability. This review will help practitioners to choose suitable training methods and may inform future research.
METHODS
Criteria for considering studies for this review
Types of studies To date, most studies investigating the effectiveness of cognitive training have used pre-post designs or relied on comparisons with alternative approaches, active control conditions or waiting list control conditions. This review focuses on randomized control trials (RCTs), for which adequate information was provided. The minimum number of measurements and assessments is two. The studies included must have been published, written in English or German, and presented in a journal article, to avoid the situation where the same or highly related data was reported in both journals and book chapters.
Types of interventions Studies were considered for this review if they describe cognitive training interventions targeting specific domains of cognitive functioning such as memory, attention, or speed. No contact control / no treatment will be defined as no training, and active control conditions will comprise non-cognitive activities, unspecific cognitive stimulation, such as art discussion (Best, Hamlett & Davis, 1992) and alternative or active control training (e.g., attention training; Scogin & Prohaska, 1992). Intervention settings were individual or group settings. When several control groups were compared to the treatment group, e.g., no treatment and multiple alternative or active controls, we considered only one comparison group respectively in the two possible comparison conditions (no contact and altervative treatment). Duration of intervention was up to one year, with at least a baseline and a post-intervention assessment reported. Types of outcome measures • For the MCI group, rates of conversion to dementia and, if applicable, rates of institutionalisation were considered, but none of the included studies provided this information; • Incidence and severity of adverse effects were considered, but none of the included studies provided this information. The following cognitive variables were considered as outcome measures: any measures of cognitive functioning, improvement, sustainability and transfer of training effects. The most important cognitive indicators were immediate and delayed recall of
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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face-name associations, visuo-spatial memory, short term memory, paired associates, and immediate and delayed recall (of words, paragraphs, stories). Outcome variables such as well-being, quality of life and everyday functioning were considered as non-cognitive outcomes and were therefore not included. Desirable outcome information from the studies relates to improvement of participants’ performance on the trained variables. Improved cognitive functioning might delay onset of pathological cognitive decline in old age or lessen the burden that impairment places on participants and significant others. Preferably, continuous scales should be used to be able to assess the full range. Studies were only included in the review if they recorded participants’ performance at least at two time points (before and after the training).
Search methods for identification of studies See Cochrane Dementia and Cognitive Improvement Group methods used in reviews. The Specialized Register of the Cochrane Dementia and Cognitive Improvement Group (CDCIG) was searched on 30 September 2007 for all years up to December 2005. This register contains records from the major healthcare databases The Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL and LILACS, and many ongoing trial databases and other grey literature sources. The following search terms were used: ’cognitive stimulation’ OR ’cognitive rehabilitation’ OR ’cognitive training’ OR ’cognitive retraining’ OR ‘cognitive re-training’ OR ’cognitive support’ OR ’memory function’ OR ’memory rehabilitation’ OR ’memory therapy’ OR ’memory aid*’ OR ’memory group*’ OR ’memory training’ OR ’memory retraining’ OR ’memory support’ OR ’memory stimulation’ OR ’memory strategy’ OR ’memory management’. The Cochrane Library, MEDLINE, EMBASE, PsycINFO and CINAHL were searched separately on 30 September 2007 to find trials with healthy people. The following search terms were used: ’cognitive stimulation’ OR ’cognitive rehabilitation’ OR ’cognitive training’ OR ’cognitive retraining’ OR ‘cognitive re-training’ OR ’cognitive support’ OR ’memory function’ OR ’memory rehabilitation’ OR ’memory therapy’ OR ’memory aid*’ OR ’memory group*’ OR ’memory training’ OR ’memory retraining’ OR ’memory support’ OR ’memory stimulation’ OR ’memory strategy’ OR ’memory management’. These search terms were used in combination with Phases 1 to 3 of the Highly sensitive search strategies for identifying reports of randomized controlled trials in MEDLINE (APPENDIX 5b, Cochrane Handbook, 2006), and all terms were searched as Title, abstract, keyword, Publication type. On 30 September 2007, the Register consisted of records from the following databases: Healthcare databases • CENTRAL: (The Cochrane Library 2006, Issue 1);
• MEDLINE (1966 to 2006/07, week 5); • EMBASE (1980 to 2006/07); • PsycINFO (1887 to 2006/08, week 1); • CINAHL (1982 to 2006/06); • SIGLE (Grey Literature in Europe) (1980 to 2005/03); • LILACS: Latin American and Caribbean Health Science Literature (http://bases.bireme.br/cgi-bin/wxislind.exe/iah/ online/?IsisScript=iah/iah.xis&base=LILACS&lang=i&form=F) (last searched 29 August 2006).
Conference roceedings • ISTP (http://portal.isiknowledge.com/portal.cgi) (Index to Scientific and Technical Proceedings) (to 29 August 2006); • INSIDE (BL database of Conference Proceedings and Journals) (to June 2000)
Theses • Index to Theses (formerly ASLIB) (http://www.theses.com/ ) (UK and Ireland theses) (1716 to 11 August 2006); • Australian Digital Theses Program (http://adt.caul.edu.au/ ): (last update 24 March 2006); • Canadian Theses and Dissertations (http:// www.collectionscanada.ca/thesescanada/index-e.html): 1989 to 28 August 2006); • DATAD - Database of African Theses and Dissertations (http://www.aau.org/datad/backgrd.htm); • Dissertation Abstract Online (USA) (http:// wwwlib.umi.com/dissertations/gateway) (1861 to 28 August 2006).
Ongoing trials
UK
• National Research Register (http://www.updatesoftware.com/projects/nrr/) (last searched issue 3/2006); • ReFeR (http://www.refer.nhs.uk/ViewWebPage.asp?Page= Home) (last searched 30 August 2006); • Current Controlled trials: Meta Register of Controlled trials (mRCT) (http://www.controlled-trials.com/) (last searched 30 August 2006) • ISRCTN Register - trials registered with a unique identifier • Action medical research • Kings College London • Laxdale Ltd • Medical Research Council (UK) • NHS Trusts Clinical Trials Register • National Health Service Research and Development Health Technology Assessment Programme (HTA)
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• National Health Service Research and Development Programme ’Time-Limited’ National Programmes • National Health Service Research and Development Regional Programmes • The Wellcome Trust • Stroke Trials Registry (http://www.strokecenter.org/trials/ index.aspx) (last searched 31 August 2006).
Netherlands
• Nederlands Trial Register (http://www.trialregister.nl/ trialreg/index.asp) (last searched 31 August 2006).
These results were supplemented by searches from January 1970 to September 2007 in PsyhInfo/Psyindex, ISI Web of Knowledge and PubMed. The search terms used were: ’memory training’, ’mnemonic training’, ’cognitive training’, ’cognitive rehabilitation’, ’cognitive intervention’, ’cognitive exercise’ in combination with ’elderly’, ’old adults’, old age’, ‘MCI’, ‘mild cognitive impairment’, ’memory complainers’, ’AACD’, ’dementia’, ’dementia treatment’, and ’dementia therapy’. After searches were completed among the major databases, reference lists from acquired studies and recent metaanalyses were examined to find additional RCTs.
Data collection and analysis USA/International
• ClinicalTrials.gov (http://www.ClinicalTrials.gov) (last searched 31 August 2006) (contains all records from http:// clinicalstudies.info.nih.gov/); • IPFMA Clinical trials Register: www.ifpma.org/ clinicaltrials.html. The Ongoing Trials database within this Register searches http://www.controlled-trials.com/isrctn, http:// www.ClinicalTrials.gov and http://www.centerwatch.com/. The ISRCTN register and Clinicaltrials.gov are searched separately. Centerwatch is very difficult to search for our purposes and no update searches have been done since 2003. • The IFPMA Trial Results databases searches a wide variety of sources among which are: • http://www.astrazenecaclinicaltrials.com (seroquel, statins) • http://www.centerwatch.com • http://www.clinicalstudyresults.org • http://clinicaltrials.gov • http://www.controlled-trials.com • http://ctr.gsk.co.uk • http://www.lillytrials.com (zyprexa) • http://www.roche-trials.com (anti-abeta antibody) • http://www.organon.com • http://www.novartisclinicaltrials.com (rivastigmine) • http://www.bayerhealthcare.com • http://trials.boehringer-ingelheim.com • http://www.cmrinteract.com • http://www.esteve.es • http://www.clinicaltrials.jp This part of the IPFMA database is searched and was last updated on 4 September 2006; • Lundbeck Clinical Trial Registry (http:// www.lundbecktrials.com) (last searched 15 August 2006); • Forest Clinical trial Registry (http:// www.forestclinicaltrials.com/) (last searched 15 August 2006). The search strategies used to identify relevant records in MEDLINE, EMBASE, PsycINFO, CINAHL and LILACS can be found in the Group’s module on The Cochrane Library.
Searches were conducted as detailed above to identify all relevant published studies, and hard copies of articles were obtained. RCTs were identified and four reviewers (MM, MA, FZ and LC) worked independently to determine which studies meet the criteria for inclusion before reaching a final consensus on which studies to include. Quality assessment The reviewers assessed the methodological quality of randomization in each trial using one of the approaches described in the Cochrane Reviewers’ Handbook (Higgins 2008): In category A (adequate), the report describes allocation of treatment by: (i) some form of centralized randomized scheme, such as having to provide details of an enrolled participant to an office by telephone to receive the treatment group allocation; (ii) some form of randomization scheme controlled by a pharmacy; (iii) numbered or coded containers, as in a pharmaceutical trial in which capsules from identical-looking numbered bottles are administrated sequentially to enrolled participants; (iv) an on-site or coded computer system, provided that the allocations were in a locked, unreadable file that could be accessed only after inputting the characteristics of an enrolled participants; or (v) if assignment envelopes were used, the report should at least specify that they were sequentially numbered, sealed, and opaque; (vi) other combinations of described elements of the process that provide assurance of adequate concealment. Category B (intermediate) is where the report describes allocation of treatment by: (i) use of a ”list” of ”table” to allocate assignments; (ii) use of ”envelopes” or ”sealed envelopes”; (iii) stating the study as ”randomized” without further detail. Category C (inadequate) is where the report describes allocation of treatment by: (i) alternation; (ii) reference to case record numbers, dates of birth, day of week, or any such approach; (iii) any allocation procedure that is transparent before assignment, such as an open list of random numbers or assignments. Empirical research has shown that lack of adequate allocation concealment is associated with bias. Trials with unclear concealment measures
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have been shown liable to yield more pronounced estimates of treatment effects than trials that have adequate measure to conceal allocation schedules, but the effect is less pronounced than inadequately concealed trials (Chalmers 1983; Schulz 1995). Trials were considered if they conformed to categories A or B, but those falling in category C were excluded. Other aspects of trial quality were not assessed by a scoring system but details of blinding, appropriateness of methods and the number of patients lost to follow-up were noted.
Data extraction Data from the RCTs selected for inclusion was extracted. The summary statistics required for each trial and each outcome for continuous data are the mean change from baseline, the standard error of the mean change, and the number of patients for each treatment group at each assessment. Where changes from baseline were not reported, the mean, standard deviation and the number of people in each treatment group at each time point was extracted if available. The baseline assessment is defined as the latest available assessment prior to randomization, but no longer than two months before. For each outcome measure, data of those who completed the trial was sought and indicated as such. Wherever possible, the data were sought irrespective of compliance, whether or not the person was subsequently deemed ineligible, or otherwise excluded from treatment or follow-up.
Data analysis We pooled studies with sufficient data, judged to be clinically homogeneous, using RevMan 5.0 software. We intended to include studies addressing or cognitive domains other than memory, but no more than one study in any given domain was identified that met our inclusion criteria. The outcomes measured may arise from ordinal rating scales. Where the rating scales used in the trials have a reasonably large number of categories (more than 10) the data were treated as continuous outcomes arising from a normal distribution. Summary statistics (n, mean and standard deviation) were used for each rating scale at each assessment time for each treatment group in each trial for change from baseline. For cross-over trials only the data from the first treatment period was used. When change from baseline results were not reported, the required summary statistics were calculated from the baseline and assessment time treatment group means and standard deviations. In this case a zero correlation between the measurements at baseline and assessment time was assumed. This method overestimates the standard deviation of the change from baseline, but this conservative approach is considered to be preferable in a meta-analysis. Meta-analysis requires the combination of data from trials that may not use the same rating scale to assess an outcome. The measure
of the treatment difference for any outcome is the weighted mean difference when the pooled trials use the same rating scale or test, and the standardized mean difference, which is the absolute mean difference divided by the pooled standard deviation when they used different rating scales or tests. The duration of the trials varied considerably. Some training interventions covered equally long time spans, but differed in intensity or vice versa. If one assumes that the intensity and frequency is the most important determinant of the occurrence of a training effect, then the difference in time span might be neglected as long as time spans do not exceed several months (as provided for in our inclusion criteria). Thus, we decided to combine all trials into the respective meta-analyses to maximize the information extracted from the database. Once more training data are available, it might be appropriate to divide the studies into smaller time periods and to conduct a separate meta-analysis for studies of different durations. Some trials might contribute data to more than one time period if multiple assessments have been made. We selected one variable from each study to represent the outcome measure and when several control groups were compared to the treatment group (i.e. several active control groups), we selected only one group for comparison. This has the advantage of not giving too much weight to one study but does minimize information extraction from the database. For binary outcomes, such as improvement or no improvement, the odds ratio was used to measure treatment effect. A weighted estimate of the typical treatment effect across trials was calculated. Overall estimates of the treatment difference are presented. In all cases the overall estimate from a fixed-effects model is presented and a test for heterogeneity using a standard chi-square statistic was performed. If, however, there is evidence of heterogeneity of the treatment effect between trials then either only homogeneous results will be pooled, or a random-effects model used (in which case the confidence intervals would be broader than those of a fixed-effects model). When studies were statistically heterogeneous (I2 test value > 50%), a random-effect model was used; otherwise a fixed-effect model was used.
RESULTS
Description of studies See: Characteristics of included studies; Characteristics of excluded studies. From the initial set of references identified by the systematic searches, a set of thirty-six studies met the inclusion criteria. Two studies were ranked as grade A and thirty-four as grade B. Thirtythree of the included studies involved healthy older people and three of them investigated people with mild cognitive impairment.
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Sample size, patients’ age, type of cognitive training, type of control condition, duration and modality of training, outcome measures, and effect sizes were evaluated and are presented in the tables on characteristics of included and excluded studies. Overall, 767 healthy older adults and 34 participants with mild cognitive impairment, 442 no contact controls and 986 controls with alternative treatments (active controls) were included in the analysis. The included studies varied in many aspects. They varied considerably in terms of number of training sessions and overall duration of the intervention: the time devoted to training sessions varied between 6 and 135 hours, and the overall period of the cognitionbased interventions between one day and one year. Less divergent, but still variable and not always indicated, were pre- to post-test intervals and training to post-test intervals. The post-treatmentassessments took mainly place immediately after training (immediately after training completion or within one week after completion). The duration of the trainings varied between a few hours and a year. Most of the interventions were conducted in a group setting with a trainer or tutor, and a minority were self-instructional or conducted on an individual basis. Cognition-based training intervention groups focused primarily on mnemotechniques and multifactorial training which combined various methods. Active alternative treatments included group discussions as well as physical training and drug treatment alone or in combination with strategy training. No contact control groups had no training at all.
Cognitive Domain
Memory
Ability subgroups
Results of the search
We identified 36 randomized controlled trials including a total of 2229 participants with an estimated mean age of 69.90 years (SD 3.53) (mean age was estimated from midpoint of the age range for those studies in which mean age was not reported). Interventions were grouped into cognitive domains (such as memory, executive function, attention and speed) and then pooled to create ability subgroups within the domains that were as homogeneous as possible. Studies providing data on training in speed of processing, attention and executive functioning were excluded due to lack of correspondence to inclusion criteria. Therefore, these domains could not be assessed and only data on memory training could be pooled for analysis. Within the memory domain, training interventions were grouped according to the following ability subgroups: face-name immediate and delayed recall, visuo-spatial memory, short term memory, paired associate learning, immediate recall and delayed recall. Data on prospective memory could not be pooled. Therefore, for studies with healthy older people, only data on immediate and delayed (face-name) recall, visuo-spatial memory, short-term memory, and paired associate learning could be pooled. Since only three studies included people with mild cognitive impairment, data pooling for this group was only possible for one of the seven outcome measures in the memory domain (immediate recall) (Table 1).
Availability of pooled data for healthy older people
People with MCI
face-name immediate recall
yes
not enough data
face-name delayed recall
yes
not enough data
visuo-spatial memory (Benton, vi- yes sual reproductions)
not enough data
short term memory (digit span)
yes
not enough data
paired associates
yes
not enough data
immediate recall (of words, para- yes graphs, stories)
yes
delayed recall (of words, para- yes graphs, stories)
not enough data
prospective memory
not enough data
not enough data
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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(Continued)
Executive Functions
semantic verbal fluency
not enough data
not enough data
phonematic verbal fluency
not enough data
not enough data
abstraction
not enough data
not enough data
inductive reasoning
not enough data
not enough data
Attention
-
not enough data
not enough data
Speed
-
not enough data
not enough data
Table 1: Overview of evaluated cognitive domains and ability subgroups. Included studies Thirty-six studies were selected for inclusion in the current metaanalysis. These studies a) included healthy normal participants or people with mild cognitive impairment, b) included a pre- and posttreatment measure of memory performance and other cognitive domains (studies that investigated long-term effects through follow-up were not included), and c) provided sufficient statistical data for the computation of effect sizes. A total of 34 research papers was retrieved, including information on 36 studies. However, pooling of studies was only possible where at least two studies covered the same intervention domain. Thus, 24 studies could be pooled with regard to outcome measures. Excluded studies Over 120 studies were excluded because they focused on patients with cognitive impairments or a diagnosis of dementia. Thirtynine studies were excluded because they were not intervention studies, were reviews, were not journal articles, or were written in neither English nor German. Reasons for excluding the rest of the studies were as follows (see table “Characteristics of exluded studies”): a) non-randomised study design (45) b) no pre-/post design (3) c) age range (7) d) missing data (17)
Risk of bias in included studies As is typical for meta-analyses on the effectiveness of interventions, there are several sources of bias in published training studies. First, there is a bias toward publishing studies or publishing
results from test instruments demonstrating significant gains after training. This may have led to the relatively small set of 36 studies over a 37-year period examining the effects of cognitive training using a randomized control design. Either it is difficult to publish the replication of an existing finding (publication bias) or the goal of most training studies is to demonstrate that individuals improve after training and determining the cause for the improvement is of secondary interest (as demonstrated by a relatively large number of excluded studies). As a consequence, published studies are more likely to contain significant improvements after training. Second, there might be a bias towards overestimating effects by using the treatment for multiple comparisons with no contact controls and one or more active control conditions. Third, outcome variables are pooled that measure the same ability but are not totally identical. Fourth, only two of the included studies reported an adequate allocation concealment or double-blind design, whereas the other studies were described as “randomized” without further detail. Considering these types of biases and the limited evidence for positive effects after combination of data in a meta-analysis, even these improvements might be overestimating the actual chances of improvement through cognitive training interventions.
Effects of interventions For calculations we used RevMan 5 (see data analysis). We identified 36 randomized controlled trials, and 24 were finally pooled including a total of 2229 participants. Interventions were grouped into cognitive domains and only data on memory training could be pooled. Therefore within the memory domain, training interventions were grouped according to outcome variables: facename immediate and delayed recall, visuo-spatial memory, short term memory, paired associates, immediate recall and delayed recall.
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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For healthy older adults, immediate and delayed verbal recall improved significantly (p1.5 standard deviations below expected performance for age, or a criterion based on a clinical interview. Our analyses demonstrate significant training gains. However, the effects were significantly better for treatment compared to no contact control in one outcome measures with sufficient data for meta-analysis, namely immediate recall. This improvement was also not specific as it did not exceed the improvement from the active control condition. Thus, it seems that alternative interventions do just as well as cognitive interventions, and the training interventions cannot be regarded as effective because they do not improve on the effects of active control conditions.
AUTHORS’ CONCLUSIONS Implications for practice As the performance improvements observed did not exceed the improvement in active control conditions, we did not find any specific training effects for any of the abilities with sufficient data for the analysis. There is evidence that cognitive interventions targeting the improvement of memory in healthy older adults and people with mild cognitive impairment are effective in producing improvement in verbal immediate and delayed recall but that these cognitive training effects are not specific, i.e., alternative interventions (active controls) do just as well as training interventions in mild cognitive impairment. It remains an open question at this point if the heterogeneity of the populations tested or the quality of the interventions may have influenced the results and we can only speculate as to whether more intensive and longer training may be needed to achieve effects larger than in active control conditions.
Implications for research Our analyses provide surprisingly little evidence for the effective-
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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ness and specificity of cognitive training interventions. Considering the sources of bias included that would typically lead to an overestimation of training effects, this argues against the effectiveness of cognitive training interventions. However, it may also suggest that future research needs to provide a more conclusive evidence base to make it possible to establish the effectiveness of cognitive interventions. First, a more standardized approach to examining the effectiveness of cognitive training is needed. Due to the heterogeneity of procedures, durations, intensities, methods of dealing with absent training participants, use of a variety of training contents, content combinations, and matching of evaluation instruments to training contents, the effects might be substantially larger if more similar studies could be pooled for the meta-analyses. Second, many training approaches include a combination of several elements, and trained individuals may respond quite differently to the different elements of the training. Thus, training effects on an individual level may be substantially higher than the group effects. Therefore, in future research, collapsing data within individuals before aggregating on a group level might provide more appropriate tests of the effectiveness of cognitive interventions. Third,
there are clearly more studies reporting the effects on rather basic abilities such as free recall compared to more complex behaviours such as prospective memory or goal-setting. This is reasonable because improvements of basic abilities are prerequisite for transfer to more complex tasks which draw on a number of these basic abilities. The ability to adjust the use of cognitive skills to perform more complex tasks may be better captured by focusing on individual learning trajectories compared to focusing on mean level changes. Fourth, there are very few studies on the effectiveness of cognitive training interventions in individuals with mild cognitive impairment of any diagnostic kind. A consistent definition or agreement on few core criteria of mild cognitive impairment may help to gather evidence more quickly because a more widespread use of this definition would make this more likely a group of research interest. Variations in type and intensity of existing training interventions are needed to gain better knowledge about the efficacy of cognitive interventions in mild cognitive impairment.
ACKNOWLEDGEMENTS
We thank the Cochrane Dementia and Cognitive Improvement Group for their support in running the searches and providing editorial support and advice in development of the protocol and review
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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REFERENCES
References to studies included in this review Ball 2002 {published data only} Ball K, Berch DB, Helmers KF, Jobe JB, Leveck MD, Marsiske M, et al.Effects of cognitive training interventions with older adults: a randomized controlled trial. JAMA 2002;288(18):2271–81. Buiza 2007 {published data only} Buiza C, Etxeberria I, Galdona N, González MF, Arriola E, López de Munain A, et al.A randomized, two-year study of the efficacy of cognitive intervention on elderly people: the Donostia Longitudinal Study. International Journal of Geriatric Psychiatry 2007;23(1):85–94. [DOI: 10.1002/ gps.1846] Caprio 1996 {published data only} Caprio-Prevette, M. D, Fry. P. S. Memory enhancement program for community-based older adults: Development and evaluation. Experimental Aging Research 1996;22: 281–303. Craik 2007 {published data only} Craik FIM, Winocur G, Palmer H, Binns MA, Edwards M, Bridges K, et al.Cognitive rehabilitation in the elderly: Effects on memory. Journal of the International Neuropsychological Society 2007;13:132–42. De Vreese 1996 {published data only} De Vreese LP, Neri M, Boiardi R, Ferrari P, Belloi L, Salvioli G. Memory training and drug therapy act differently on memory and metamemory functioning: Evidence from a pilot study. Archives of Gerontology and Geriatrics 1996; Suppl 5:9–22. Derwinger 2005 {published data only} Derwinger A, Stigsdotter Neely A, MacDonald S, Backman L. Forgetting numbers in old age: strategy and learning speed matter. Gerontology 2005;51(4):277–84. Dunlosky 2007 study 2 {published data only} Dunlosky J, Cavallini E, Roth H, McGuire CL, Vecchi T, Hertzog C. Do self-monitoring interventions improve older adult learning?. Journal of Gerontology 2007;62B(Special Issue):70–76. Dunlosky 2007 study1 {published data only} Dunlosky J, Cavallini E, Roth H, McGuire CL, Vecchi T, Hertzog C. Do self-monitoring interventions improve older adult learning?. Journal of Gerontology 2007;62B(Special Issue):70–76. Edwards 2005 {published data only} Edwards JD, Wadley VG, Vance DE, Wood K, Roenker DL, Ball KK. The impact of speed of processing training on cognitive and everyday performance. Aging and Mental Health 2005;9(3):262–71.
Fabre 2002 {published data only} Fabre C, Chamari K, Mucci P, Massé-Biron J, Préfaut C. Improvement of cognitive function by mental and/or individualized aerobic training in healthy elderly subjects. International Journal of Sports Medicine 2002;23:415–25. Flynn 1990 {published data only} Flynn TM, Storandt M. Supplemental group discussions in memory training for older adults. Psychology and Aging 1990;5(2):178–81. Gratzinger 1990 {published data only} Gratzinger P, Sheikh JI, Friedman L, Yesavage JA. Cognitive interventions to improve face-name recall: The role of personality trait differences. Developmental Psychology 1990; 26(6):889–93. Hill 1987 {published data only} Hill RD, Sheikh JI, Yesavage J. The effect of mnemonic training on perceived recall confidence in the elderly. Experimental Aging Research 1987;13(4):185–8. Hill 1988 {published data only} Hill RD, Sheikh JI, Yesavage J. Pretraining enhances mnemonic training in elderly adults. Experimental Aging Research 1988;14(4):207–11. Hill 1990 {published data only} Hill RD, Storandt M, Simeone C. The effects of memory skills training and incentives on free recall in older learners. Journal of Gerontology: Psychological Sciences 1990;45: 227–232. Hill 1991 {published data only} Hill RD, Allen C, McWhorter P. Stories as a mnemonic aid for older learners. Psychology and Aging 1991;6:484–6. Levine 2007 {published data only} Levine B, Stuss DT, Winocur G, Binns MA, Fahy L, Mandic M, et al.Cognitive rehabilitation in the elderly: Effects on strategic behavior in relation to goal management. Journal of the International Neuropsychological Society 2007;13:143–52. Mahncke 2006 {published data only} Mahncke HW, Connor BB, Appelman J, Ahsanuddin ON, Hardy J, Wood RA, et al.Memory enhancement in healthy older adults using a brain plasticity-based training program: a randomized, controlled study. Proceedings of the National Academy of Sciences 2006;103(33):12523–8. Margrett 2006 {published data only} Margrett JA, Willis SL. In-home cognitive training with older married couples: Individual versus collaborative learning. Aging, Neurpsychology, and Cognition 2006;13: 173–95. Piccolini 1992 {published data only} Piccolini C, Amadio L, Spazzafumo L, Moroni S, Freddi A. The effects of a rehabilitation program with
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mnemotechniques on institutionalized elderly subjects. Archives of Gerontology and Geriatrics 1992;15:141–149. Rapp 2002 {published data only} Rapp S, Brenes G, Marsh AP. Memory enhancement training for older adults with mild cognitive impairment: a preliminary study. Aging & Mental Health 2002;6(1):5–11. Rasmusson 1999 {published data only} Rasmusson DX, Rebok GW, Bylsma FW, Brandt J. Effects of three types of memory training in normal elderly. Aging, Neuropsychology and Cognition 1999;6:56–66. Rozzini 2007 {published data only} Rozzini, L, Costardi, D, Vicini Chilovi, B, Franzoni, S, Trabucchi, M, Padovani, A. Efficacy of cognitive rehabilitation in patients with mild cognitive impairment treated with cholinesterase inhibitors. International Journal of Geriatric Psychiatry 2007;22(4):356–360. [DOI: 10.1002/gps.1681] Schaffer 1992 {published data only} Schaffer G, Poon L. Individual variability in memory training with the elderly. Educational Gerontology 1982;8: 217–29. Scogin 1985 {published data only} Scogin F, Storandt M, Lott L. Memory-skills training, memory complaints, and depression in older adults. Journal of Gerontology 1985;40:562–8. Scogin 1992 {published data only} Scogin, Prohaska, Weeks. The efficacy of self-taught memory training for community-dwelling older adults. Educational Gerontology 1992;18:751–66. Stigsdotter 1989 {published data only} Stigsdotter A, Bäckman L. Multifactorial memory training with older adults: How to foster maintenance of improved performance. Gerontology 1989;35:260–7. Stigsdotter 1993 study 1 {published data only} Stigsdotter NA, Bäckman L. Long-term maintenance of gains from memory training in in older adults: Two 3.5year follow-up studies. Journal of Gerontolgy: Psychological Sciences 1993;48(5):233–237. Stigsdotter 1993 study 2 {published data only} Stigsdotter NA, Bäckman L. Long-term maintenance of gains from memory training in older adults: Two 31/2year follow-up studies. Journal of Gerontology: Psychological Sciences 1993;48(5):233–237. Stigsdotter 1995 {published data only} Stigsdotter NA, Bäckman L. Effects of multifactorial memory training in old age: generalizability across tasks and individuals. Journal of Gerontology 1995;50B(3):134–40. Valentijn 2005 {published data only} Valentijn SAM, van Hooren SAH, Bosma H, Touw DM, Jolles J, van Boxtel MPJ, et al.The effect of two types of memory training on subjective and objective memory performance in healthy individuals aged 55 years and older: a randomized controlled trial. Patient Education and Counselling 2005;57:106–14.
Yesavage 1990 {published data only} Yesavage JA, Sheikh JI, Friedman L, Tanke E. Learning mnemonics: roles of aging and subtle cognitive impairment. Psychol Aging 1990;5:133–7.
References to studies excluded from this review Andrewes 1996 {published data only} Andrewes DG, Kinsella G, Murphy M. Using a memory handbook to improve everyday memory in community-dwelling older adults with memory complaints. Experimental Aging Research 1996;22:305–22. Anschutz 1985 {published data only} Anschutz L, Camp CJ, Markley RP, Kramer JJ. Maintenance and generalization of mnemonics for grocery shopping by older adults. Experimental Aging Research 1985;11(3): 157–60. Anschutz 1987 {published data only} Anschutz, L, Camp, C. J, Markley, R. P, & Kramer, J. J. Remembering mnemonics: a three-year follow-up on the effects of mnemonics training in elderly adults. Experimental Aging Research 1987;13(3):141–143. [DOI: 10.1080/03610738708259315] Baldelli 1991 {published data only} Baldelli, M.V, Toschi, A, Ayyud, N, Spanó, A, Andermarcher E. The elderly and memory training: No differences were encountered between the two sexes. Archives of Gerontology and Geriatrics 1991;Supplement(2):147–150. Baltes 1988 {published data only} Baltes PB, Kliegl R, Dittmann-Kohli F. On the locus of training gains in research on the plasticity of fluid intelligence in old age. Journal of Educational Psychology 1988;80(3):392–400. Baltes 1989 {published data only} Baltes, P.B, Sowarka, D, Kliegl. R. Cognitive training research on fluid intelligence in old age: What can older adults achieve by themselves?. Psychology and Aging 1989;4 (2):217–221. Belleville 2006 {published data only} Belleville, S, Gilbert, B, Fontaine, F, Gagnon, L, Ménard, E, Gauthier. S. Improvement of episodic memory in personsn with mild cognitive impairment and healthy oder adults: evidence from a cognitive intervention program. Dementia and Geriatric Cognitive Disorders 2006;22:486–499. Best 1992 {published data only} Best, Hamlett, Davis. Memory complaint and memory performance in the elderly: the effects of memory skills training and expectancy change. Applied Cognitive Psychology 1992;6(5):405–416. [DOI: 10.1002/acp.2350060505] Bond 2000 {published data only} Bond, G.E, Wolf-Wilets, V, Fiedler, F.E, & Burr, R.L. Computer-aided cognitive training of the aged: a pilot study. Clinical Gerontologist 2000;22(2):19–42. Boron 2007 {published data only} Boron, J.B, Turiano, N.A, Willis, S.L, Schaie. W.K. Effects on cognitive training on change in accuracy in inductive
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reasoning ability. Journal of Gerontology: Psychological Sciences 2007;62B(3):179–186. Boron, J.B, Willis, S.L, Schaie. K.W. Cognitive training gain as a predictor of mental status. Journal of Gerontology: Psychological Sciences 2007;62B(1):45–52. Brooks 1993 {published data only} Brooks, J.O. 3rd, Friedman, L, Yesavage, J.A. A study of the problems older adults encounter when using a mnemonic technique. International Psychogeriatrics 1993;5(1):57–65. [DOI: 10.1017/S1041610293001395] Brooks 1999 {published data only} Brooks, J.O. III, Friedman, L, Pearman, A.M, Yesavage. J.A. Mnemonic training in older adults: effects of age, length of training, and type of cognitive retraining. International Psychogeriatrics 1999;11(1):75–84. Calero 1997 {published data only} Calero MD, Garcia-Berbén TM. A self-training program in inductive reasoning for low-education elderly: Tutorguided training versus self-training. Archives of Gerontology and Geriatrics 1997;24:249–59. Cavallini 2002 {published data only} Cavallini, E, Pagnin, A, & Vecchi, T. The rehabilitation of memory in old age: effects of mnemonics and metacognition in strategic training. Clinical Gerontologist 2002;26(1-2): 125–141. [DOI: doi:10.1016/j.pec.2006.07.010] Cavallini 2003 {published data only} Cavallini, E, Pagnin, A, Vecchi. T. Aging and everyday memory: the beneficial effect of memory training. Archives of Gerontology and Geriatrics 2003;37(3):241–257. [DOI: 10.1016/S0167-4943(03)00063-3] Cerella 2006 {published data only} Cerella, J, Onyper, S.V, Hoyer. W.J. The associativememory basis of cognitive skill learning: Adult age differences. Psychology and Aging 2006;21(3):483–498. Cipriani 2006 {published data only} Cipriani, G, Bianchetti, A, & Trabucchi, M. Outcomes of a computer-based cognitive rehabilitation program on Alzheimer’s disease patients compared with those on patients affected by mild cognitive impairment. Archives of Gerontology and Geriatrics 2006;43(3):327–333. [DOI: 10.1016/j.archger.2005.12.003] De Vreese 1998 {published data only} De Vreese, L. P, Belloi, L, Iacono, S, Finelli, C, Neri, M. Memory training programs in memory complainers: Efficacy on objective and subjective memory functioning.. Archives of Gerontology and Geriatrics. 1998;Suppl. 6: 141–154. Derwinger 2003 {published data only} Derwinger, A, Stigsdotter Neely, A, Persson, M, Hill, R.D, & Backman L. (2003). . Aging, Neuropsychology, Cognition. 10, 202-214. Remembering numbers in old age: mnemonic training versus self-generated strategy training. Aging, Neuropsychology and Cognition 2003;10(3): 202–214.
Derwinger 2005 b {published data only} Derwinger S, Stigsdotter NA, Bäckman L. Design your own memory strategies! Self-generated strategy training versus mnemonic training in old age: an 8 month followup. Neuropsychological Rehabilitation 2005;15(1):37–54. [DOI: 10.1080/09602010343000336] Dittman-Kohli 1991 {published data only} Dittmann-Kohli, F, Lachman, M.E, Kliegl, R, Baltes. P.B. Effects of cognitive training and testing on intellectual efficacy beliefs in elderly adults. Journal of Gerontology 1991;46(4):162–164. Erickson 2007 {published data only} Erickson, K.I, Colcombe, S.J, Wadhwa, R, Bherer, L, Peterson, M.S, Scalf, P.E, Kim, J.S, Alvarado, M, Kramer, A.F. Training-induced plasticity in older adults: Effects of training on hemispheric asymmetry. Neurobiology of Aging 2007;28(2):272–283. [DOI: 10.1016/ j.neurobiolaging.2005.12.012] Fernandez 2005 {published data only} Fernández-Ballesteros, R, Calero. M.D. (1995). Training effects on intelligence of older persons. Archives of Gerontology, Geriatrics. 20, 135-148. Training effects on intelligence of older persons. Archives of Gerontology and Geriatrics 1995;20(2):135–148. [DOI: 10.1016/ 0167-4943(94)00591-T] Finkel 1989 {published data only} Finkel, S.I, Yesavage. J.A. Learning mnemonic: A preliminary evaluation of a computer-aided instruction package for the elderly. Experimental Aging Research 1989; 15(3-4):199–201. [DOI: 10.1074/jbc.M202849200] Fleischmann 1985 {published data only} Fleischmann, U.M. Gedächtnisbezogene Förderung im hohen Lebensalter. Die Rehabilitation 1985;24(1):36–38. Gunther 2003 {published data only} Günther VK, Schäfer P, Holzner BJ, Kemmler GW. Longterm improvements in cognitive performance through computer-assisted cognitive training: a pilot study in a residential home for older people. Aging & Mental Health 2003;7:200–6. Hill 1989 {published data only} Hill, R.D, Yesavage, J.A, Sheikh, J, & Friedman, L. Mental status as a predictor of response memory training in older adults. Educational Gerontology 1989;15(6):633–639. [DOI: 10.1080/0380127890150607] Israel 1998 {published data only} Israel, L, Myslinski, M, Kozarevic. D. Nootropic treatment and combined therapy in age-associated memory impairment. Archives of Gerontology and Geriatrics 1998;26 (S1):269–274. [DOI: 10.1016/S0167-4943(98)80038-1] Johnston 1989 {published data only} Johnston, L, Gueldner. S.H. Remember when...? Using mnemonics to boost memory in the elderly. Journal of Gerontological Nursing 1989;15(8):22–26. Kramer 1995 {published data only} Kramer, A.R, Larish, J.F, Strayer. D.L. Training for attentional control in dual task settings: A comparison of
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young and old adults. Journal of Experimental Psychology: Applied 1995;1(1):50–76. Labouvie-Vief 1976 {published data only} Labouvie-Vief, G, Gonda. J.N. Cognitive strategy training and intellectual performance in the elderly. Journal of Gerontology 1976;31(3):327–332. [DOI: 10.1093/geronj/ 31.3.327] Lachman 1992 {published data only} Lachman, Weaver, Bandura, Elliot, Lewkowicz. Improving memory and control beliefs through cognitive restructuring and self-generated strategies. Journal of Gerontology: Psychological Sciences 1992;47(5):293–299. Martin 1998 {published data only} Martin, M, Kayser. N. (1998), 31, 91-103. Das modulare Gedächtnistraining für ältere Erwachsene: Konzeption und Erprobung. Zeitschrift für Gerontologie und Geriatrie 1998; 31(1):91–103. McKitrick 1999 {published data only} McKitrick, L.A, Friedman, L.F, Brooks, J.O. 3rd, Pearman, A, Kraemer, H.C, Yesavage, J.A. Predicting response of older adults to mnemonic training: who will benefit?. International Psychogeriatrics 1999;11(3):289–300. [DOI: 10.1017/S1041610299005852] Mohs 1998 {published data only} Mohs, R.C, Ashman, T.A, Jantzen, K, Albert, M, Brandt, J, Gordon, B, Rasmusson, X, Grossman, M, Jacobs, D, Stern. Y. A study of the efficacy of a comprehensive memory enhancement program in healthy elderly persons. Psychiatry Research 1998;77(3):183–195. [DOI: 10.1016/ S0165-1781(98)00003-1] Neils-Strunjas 1997 {published data only} Neils-Strunjas, J, Ollier, L, Thomas, K, Thomas. G. A comparison of two training methods for teaching name-face associations to elderly subjects with self-reported memory loss. Brain and Cognition 1997;35:308–426. Olazarán 2004 {published data only} Olazarán, J, Muñiz, R, Reisberg, B, Peña-Casanova, J, del Ser, T, Cruz-Jentoft, A.J, &, et al.Benefits of cognitivemotor intervention in MCI and mild to moderate Alzheimer disease. Neurology 2004;63:2348–2353. Onyper 2006 {published data only} Onyper SV, Hoyer WJ, Cerella J. Determinants of retrieval solutions during cognitive skill training: Source confusions. Memory and Cognition 2006;34(3):538–549. Oswald 1996 {published data only} Oswald, W.D, Rupprecht, R, Gunzelmann, T, Tritt. K. The SIMA-project: Effects of 1 year cognitive and psychomotor training on cognitive abilities of the elderly. Behavioural Brain Research 1996;78(1):62–72. [DOI: 10.1016/ 0166-4328(95)00219-7] Oswald 1998 {published data only} Oswald, W.D, Hagen, B, Rupprecht. R. Bedingungen der Erhaltung und Förderung von Selbständigkeit im höheren Lebensalter (SIMA) - Teil X: Verlaufsanalyse des kognitiven
Status. Zeitschrift für Gerontopsychologie und -psychiatrie 1998;11(3):202–221. Oswald 2002 {published data only} Oswald, W.D, Hagen, B, Rupprecht, R, Gunzelmann. T. (2002). Conditions of conservation and promoting independence in old-age (SIMA) Part XVII: Summary the long-term training effects [Bedingungen der Erhaltung und Förderung von Selbständigkeit im höheren Lebensalter (SIMA). Teil XVII: Zusammenfassende Darstellung der langfristigen Trainingseffekte]. Zeitschrift für Gerontopsychologie und - psychiatrie 2002;15(1):13–31. Oswald 2006 {published data only} Oswald, W.D, Gunzelmann, T, Rupprecht, R, Hagen. B. Differential effects of single versus combined cognitive and physical training with older adults: the SimA study in a 5-year perspective.. European Journal of Aging 2006;3(4): 179–192. [DOI: 10.1007/s10433-006-0035-z] Oswald 2007 {published data only} Oswald, W.D, Gunzelmann, T, Ackermann. A. Effects of a multimodal activation program (SimA-P) in residents of nursing homes. European Review of Aging and Physical Activity 2007;4(2):91–102. [DOI: 10.1007/ s11556-007-0025-y] Ott-Chervet 1998 {published data only} Ott-Chervet, C, Rüegger-Frey, B, Klaghofer, R, & Six, P. Evaluation eines computergestützten kognitiven Trainings mit hochbetagten Patienten eines geriatrischen Krankenhauses. Zeitschrift für Gerontopsychologie und psychiatrie 1998;1(1):13–23. Panza 1996 {published data only} Panza, F, Solfrizzi, V, Mastroianni, F, Nardo, G.A, Cigliola, F, & Capurso, A. A rehabilitation program for mild memory impairments. Archives of Gerontology and Geriatrics 1996; Suppl. 5:51–55. Paxton 2006 {published data only} Paxton, J.L, Barch, D.M, Storandt, M, Braver. T.S. Effects of environmental support and strategy training on older adults’ use of context. Psychology and Aging 2006;21(3): 499–509. Rebok 1989 {published data only} Rebok, G.W, Balcerak. L.J. Memory self-efficacy and performance differences in young and old adults: the effect of mnemonic training. Developmental Psychology 1989;25 (5):714–721. Rebok 1996 {published data only} Rebok, G.W, Rasmusson, D.X, Brandt. J. Prospects for computerized memory training in normal elderly: Effects of practice on explicit and implicit memory tasks. Applied Cognitive Psychology 1996;10(3):211–223. [DOI: 10.1002/ acp.2350100301] Rebok 1997 {published data only} Rebok, G.W, Rasmusson, D.X, Bylsma, F.W, & Brandt, J. Memory improvement tapes: how effective for elderly adults?. Aging, Neuropsychology and Cognition 1997;4(4): 304–311. [DOI: 10.1080/13825589708256655]
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Saczynski 1992 {published data only} Saczynski, J.S, Willis, S.L, Schaie K.W. Strategy use in reasoning training with older adults. Aging, Neuropsychology and Cognition 2002;9(1):48–60. Schaie 1987 {published data only} Schaie, K.W, Willis, S.L, Hertzog, Ch, Schulenberg. J.E. Effects of cognitive training on primary mental ability structure. Psychology and Aging 1987;2(3):233–242. Schmidt 1999 {published data only} Schmidt IW, Dijkstra HT, Berg IJ, Deelman BG. Memory training for remembering names in older adults. Clinical Gerontologist 1999;20(2):57–73. Schmidt 2001 {published data only} Schmidt IW, Berg, IJ, Deelman BG. Prospective memory training in older adults. Educational Gerontology 2001;27 (6):455–78. Schmitt 1981 {published data only} Schmitt F.A, Murphy M.D, Sanders R.E. Training older adult free recall rehearsal strategies. Journal of Gerontology 1981;36(3):329–337. Scogin 1988 {published data only} Scogin, F, Bienias. J.L. A three-year follow-up of older adult participants in a memory-skills training program. Psychology and Aging 1988;3(4):334–337. Sheikh 1986 {published data only} Sheikh, J.I, Hill. R.D, Yesavage. J.A. Long-term efficacy of cognitive training for age-associated memory impairment: A six-month follow-up study. Developmental Neuropsychology 1986;2(4):413–421. Sitzer 2006 {published data only} Sitzer, DI, Twamley EW, & Jeste DV. Cognitive training in Alzheimer’s disease: a meta-analysis of the literature. Acta Psychiatrica Scandinavica 2006;114:75–90. Small 2006 {published data only} Small, G.W, Silverman, D.H, Siddarth, P, Ercoli, L.M, Miller, K.J, Lavretsky, H, Wright, B.C, Bookheimer, S.Y, Barrio, J.R, Phelps, M.E. Effects of a 14-day healthy longevity lifestyle program on cognition and brain function. American Journal of Geriatrics and Psychiatry 2006;14(6): 538–545. [DOI: 10.1097/01.JGP.0000219279.72210.ca] Stine-Morrow 2007 {published data only} Stine-Morrow, E.A.L, Parisi, J.M, Morrow, D.G, Greene, J, Park. D.C. An engagement model of cognitive optimization through adulthood. Journal of Gerontology 2007;62B(SI1): 62–69. Talassi 2007 {published data only} Talassi, E, Guerreschi, M, Feriani, F, Fedi, V, Bianchetti, A, & Trabucchi, M. Effectiveness of a cognitive rehabilitation program in mild dementia (MD) and mild cognitive impairment (MCI) a case control study. Archives of Gerontology and Geriatrics 2007;Suppl. 1:391–399. Valenzuela 2003 {published data only} Valenzuela, M.J, Jones, M, Wen, W, Rae, C, Graham, S, Shnier, R, Sachdev. P. Memory training alters hippocampal
neurochemistry in healthy elderly. Neuroreport 2003;14 (10):1333–1337. Van Gerven 2003 {published data only} Van Gerven, P.W.M, Paas, F, van Merrienboer, J.J.G, Hendricks, M, Schmidt. H.G. The efficacy of multimedia learning into old age. British Journal of Educational Psychology 2003;73(4):489–505. [DOI: 10.1348/ 000709903322591208] Van Gerven 2006 {published data only} Van Gerven, P.W.M, Paas, F, van Merrienboer, J.J.G, Schmidt. H.G. Modality and variability as factors in training the elderly. Applied Cognitive Psychology 2006;20 (3):311–320. [DOI: 10.1002/acp.1247] Van Hooren 2007 {published data only} Van Hooren, S.A.H, Valentijn, S.A.M, Bosma, H, Ponds, R.W.H.M, Boxtel, M.P.J, Levine, B, Robertson, I.& Jolles, J. Effect of a structured course involving goal management training in older adults: A randomised controlled trial. Patient Education and Counseling 2007;65(2):205–213. [DOI: 10.1016/j.pec.2006.07.010] Wadley 2006 {published data only} Wadley, V.G, Benz, R.L, Ball, K.K, Roender, D.L, Edwards, J.D, Vance. D.E. Development and evaluation of homebased speed-of-processing training for older adults. Archives of Physical Medecine and Rehabilitation 2006;87(6): 757–763. [DOI: 10.1016/j.apmr.2006.02.027] Wenisch 2007 {published data only} Wenisch E, Cantegreil-Kalen I, De Rotrou J, Garrigue P, Moulin F, Batouche F, et al.Cognitive stimulaton intervention for elders with mild cognitive impairment compared with normal aged subjects preliminary results.. Aging Clinical and Experimental Research 2007;19(4): 316–322. Werner 2000 {published data only} Werner P. Assessing the effectiveness of a memory club for elderly persons suffering from mild cognitive impairment. Clinical Gerontologist 2000;22(1):3–14. West 1992 {published data only} West, R. L, Crook. T. H. Video training of imagery for mature adults. Applied Cognitive Psychology 1992;6(4): 307–320. [DOI: 10.1002/acp.2350060404] Willis 1986 {published data only} Willis, S.L, Schaie. K.W. Training the elderly on the ability factors of spatial orientation and inductive reasoning. Psychology and Aging 1986;1(3):239–247. Willis 1988 {published data only} Willis, S.L, Schaie. K.W. Gender differences in spatial ability in old age: Longitudinal and intervention findings. Sex Roles 1988;81(3-4):189–203. Willis 1990 {published data only} Willis, S.L, Nesselroade. C.S. Long-term effects of fluid ability training in old-age. Developmental Psychology 1990; 26(6):905–910. [DOI: 10.1037/0012-1649.26.6.905]
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Willis 2006 {published data only} Willis, S.L, Tennstedt, S.L, Marsiske, M, Ball, K, Elias, J, Mann Koepke, K, Morris, J.N, Rebok, G.W, Unverzagt, F.W, Stoddard, A.M, Wright. E. Long-term effects of cognitive training on everyday functional outcomes in older adults. Journal of the American Medical Association 2006; 296(23):2805–2814. Winningham 2003 {published data only} Winningham, R.G, Anunsen, R, Hanson, L.M, Laux, L, Kaus, K.D, & Reifers, A. MemAerobics: A cognitive intervention to improve memory ability and reduce depression in older adults. Journal of Mental Health and Aging 2003;9(2):182–192. Winocur 2007 {published data only} Winocur, G, Palmer, H, Dawson, D, Binns, M.A, Bridges, K, Stuss. D.T. Cognitive rehabilitation in the elderly: An evaluation of psychosocial factors. Journal of the International Neuropsychological Society 2007;13(1): 153–165. [DOI: 10.1017/S135561770707018X] Wolinksy 2006 b {published data only} Wolinsky, F.D, Unverzagt, F.W, Smith, D.M, Jones, R, Stoddard, A, Tennstedt. S.L. (2006), 61A(12), 1324-1329. The ACTIVE cognitive training trial and health-related quality of life: protection that lasts for 5 years. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences 2006;61A(12):1324–1329. Wolinsky 2006 a {published data only} Wolinsky, F.D, Unverzagt, F.W, Smith, D.M, Jones, R, Stoddard, A, Tennstedt. S.L. The effects of the ACTIVE cognitive training trial on clinically relevant declines in health-related quality of life. Journals of Gerontology: Social Sciences 2006;61B(5):281–287. Wood 1987 {published data only} Wood, L.E, Pratt. J.D. Pegword mnemonic as an aid to memory in the elderly: a comparison of four age groups. Educational Gerontology 1987;13(4):325–339. Yesavage 1983 a {published data only} Yesavage, J.A, Rose, T.L, Bower. G.H. Interactive imagery and affective judgement improve face-name learning in the elderly.. Journal of Gerontology 1983;38(2):197–203. [DOI: 10.1093/geronj/38.2.197] Yesavage 1983 b {published data only} Yesavage, J.A. Imagery pretraining and memory training in the elderly. Gerontology 1983;29(4):271–275. [DOI: DOI: 10.1159/000213126]
Zarit 1981 {published data only} Zarit, S.H, Cole, K.D, Guider. R.L. Memory training strategies and subjective complaints of memory in the aged. The Gerontologist 1981;21(2):158–164. [DOI: 10.1093/ geront/21.2.158]
Additional references APA 1987 American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 3rd Edition. Washington, DC: American Psychiatric Association, 1987. Busse 2003 Busse A, Bischkopf J, Riedel-Heller SG, et al.Mild cognitive impairment: prevalence and predictive validity according to current approaches. Acta Neurologica Scandinavia 2003; 108:71–81. Chalmers 1983 Chalmers TC, Celano P, Sacks HS, Smith H. Bais in treatment assignment in controlled clinical trials. New England Journal of Medicine 1983;309:1358–61. Clare 2003 Clare L. Cognitive training and cognitive rehabilitation for people with early-stage dementia. Reviews in Clinical Gerontology 2003;13:75–83. Crook 1986 Crook T, Bartus RT, Ferris SH, Whitehouse P, Cohen GD, Gershon S. Age-associated memory impairment: proposed diagnostic criteria and measures of clinical change. Developmental Neuropsychology 1986;2:261–76. Graham 1997 Graham JE, Rockwood K, Beattie BL, Eastwood R, Gauthier S, Tuokko H, McDowell I. Prevalence and severity of cognitive impairment with and without dementia in an elderly population. Lancet 1997;349:1793–96. Higgins 2008 Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.0.0 [updated February 2008]. The Cochrane Collaboration, 2008. Available from www.cochrane-handbook.org. Chichester, UK: John Wiley & Sons, Ltd. Hoyer 2006 Hoyer WJ, Verhaeghen P. Memory aging. In: Birren JE, Schaie KW editor(s). Handbook of the psychology of aging. 6th Edition. Amsterdam: Academic Press, 2006:209–32.
Yesavage 1983 c {published data only} Yesavage, J.A, Rose. T.L. Concentration and mnemonic training in elderly subjects with memory complaints: a study of combined therapy and order effects. Psychiatry Research 1983;9(2):157–167. [DOI: 10.1016/0165-1781 (83)90037-9]
Hultsch 1999 Hultsch DF, Hertzog C, Small BJ, Dixon RA. Use it or lose it: engaged lifestyle as a buffer of cognitive decline in aging? . Psychology and Aging 1999;14:245–263.
Yesavage 1984 {published data only} Yesavage, J. A, & Jacob, R. Effects of relaxation and mnemonics on memory, attention and anxiety in the elderly. Experimental Aging Research 1984;10(4):211–214. [DOI: 10.1080/03610738408258467]
Jungwirth 2005 Jungwirth S, Weissgram S, Zehetmayer S, et al.VITA: subtypes of mild cognitive impairment in a communitybased cohort at the age of 75 years. International Journal of Geriatric Psychiatry 2005;20:452–8.
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Kliegl 1989 Kliegl R, Smith J, Baltes PB. Testing-the-Limits and the Study of Adult Age-Differences in Cognitive Plasticity of a Mnemonic Skill. Developmental Psychology 1989;25(2): 247–56. Kral 1962 Kral VA. [Senescent forgetfulness: Benign and malignant]. Le Journal de l’Association Médicale Canadienne 1962;86: 257–60. Kratz 2002 Kratz B. Drei Aspekte des diagnostischen Konzepts der leichten kognitiven Beeinträchtigung im Alter. Dissertationsschrift, University of Heidelberg 2002. Kumar 2005 Kumar R, Dear KBG, Christensen H, Ilschner S, Jorm AF, Meslin C, Rosenman SJ, Sachdev PS. Prevalence of mild cognitive impairment in 60-to 64-year-old communitydwelling individuals: The Personality and Total Health through Life 60+study. Dementia and Geriatric Cognitive Disorders 2005;19:67–74. Larrieu 2002 Larrieu S, Letenneur L, Orgogozo JM, Fabrigoule C, Amieva H, Le Carret N, Barberger-Gateau P, Dartigues JF. Incidence and outcome of mild cognitive impairment in a population-based prospective cohort. Neurology 2002;59: 1594–9. Manly 2005 Manly JJ, Bell-McGinty S, Tang MX, et al.Implementing diagnostic criteria and estimating frequency of mild cognitive impairment in an urban community. Archives of Neurology 2005;62:1739–46. Nyberg 2005 Nyberg L. Cognitive training in healthy aging: A cognitive neuroscience perspective. In: Cabeza R, Nyberg L, Park DC editor(s). Cognitive neuroscience of aging. New York: Oxford University Press, 2005:309–21. Petersen 2001 Petersen RC, Doody R, Kurz A, Mohs RC, Morris JC, Rabins PV, Ritchie K, Rossor M, Thal L, Winblad B. Current concepts in Mild Cognitive Impairment. Archives of Neurology 2001;58:1985–92. Purser 2005 Purser JL, Fillenbaum GG, Pieper CF, et al.Mild cognitive impairment and 10-year trajectories of disability in the Iowa
established populations for epidemiologic studies of the elderly cohort. Journal of the American Geriatrics Society 2005;53:1966–72. Schooler 2001 Schooler C, Mulatu MS. The reciprocal effects of leisure time activities and intellectual functioning in older people: a longitudinal analysis. Psychology and Aging 2001;16: 466–82. Schulz 1995 Schulz KF, Chalmers I, Hayes RJ, Altman D. Empirical evidence of bias. Journal of the American Medical Association 1995;273:408–12. Singer 2003 Singer T, Lindenberger U, Baltes PB. Plasticity of memory for new learning in very old age: A story of major loss?. Psychology and Aging 2003;18:306–17. Stern 2002 Stern Y. What is cognitive reserve? Theory and research application of the reserve concept. Journal of the International Neuropsychological Society 2002;8:448–60. Unverzagt 2007 Unverzagt FW, Kasten L, Johnson KE, Rebok GW, Marsiske M, Mann Koepke K, Elias JW, et al.Effect of memory impairment on training outcomes in ACTIVE. Journal of the International Neuropsychological Society 2007;13(6): 953–960. Verhaeghen 1992 Verhaeghen P, Marcoen A, Goossens L. Improving memory performance in the aged through mnemonic training: A meta-analytic study. Psychology and Aging 1992;7:242–51. Willis 2001 Willis SL. Methodological issues in behavioural intervention research with the elderly. In: Birren JE, Schaie KW editor (s). Handbook of the psychology of aging. 5th Edition. San Diego, CA: Academic Press, 2001:78–108. Wilson 2002 Wilson RS, Mendes de Leon CF, Barnes LL, et al.Participation in cognitively stimulating activities and risk of incident Alzheimer disease. Journal of the American Medical Association 2002;287:742–8. ∗ Indicates the major publication for the study
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CHARACTERISTICS OF STUDIES Characteristics of included studies [ordered by study ID] Ball 2002 Methods
single-blind design; no contact control group;training lasts 5-6 weeks
Participants
- n no contact control=704 - n memory=711 - n problem=705
Interventions
problem-solving training, memory strategies, speed training
Outcomes
problem solving, verbal episodic memory, speed;
Notes Buiza 2007 Methods
double-blind design; 2 years (total of 180 sessions), t1=baseline, then every 6 months
Participants
- n exp structured 1=85 - n exp unstructured 2=68
Interventions
attention, orientation, memory, language, visuoconstruction, visuomanual coordination, praxis
Outcomes
Luria, speed (TMT), visuomanual coordination, short term memory, immediate recall, recent logic execution memory, abstraction proverbs, phonematic fluency, IADL
Notes
data available: initial, annual, biannual
Caprio 1996 Methods
memory training versus alternative training; no no contact control group
Participants
age range 65-76 years
Interventions
cognitive restructuration technique versus traditional memory training
Outcomes
Guild Memory Test, supermarket test; subjective memory tests and Geriatric Depression Scale
Notes
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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Craik 2007 Methods
cross-over design; early training group vs. late training; group (before cross-over); baseline, post-test after 3 months; 4 weeks duration
Participants
n early =29 n late(control)=20
Interventions
memory skills training
Outcomes
alpha span (working memory) total score, Brown-Peterson: secondary memory, primary memory, 0s delay, primary memory ,3s delay
Notes De Vreese 1996 Methods
4 groups: - memory training - drug treatment - drug + memory - no contact control
Participants
MCI patients: a score > 25 adjusted for age and schooling (Measso et al., 1993) on the mini-mental state examination (MMSE, Folstein et al., 1975); (f ) no clinically relevant depression as disclosed by a score < 16 on the geriatric depression scale (GDS, Yesavage et al., 1983); (g) presence of impaired objective memory resulting in a score < 15. 76 on the story recall test (De Renzi, 1977) and/or significant memory complaints evinced by a score > 20 on the cognitive difficulties scale (CDS, MacNair and Kahn, 1983) n memory training=10 n drug treatment=7 n memory training and drug treatment=10 n control group=8
Interventions
drug treatment and memory training
Outcomes
Randt Memory Test:acquisition, delayed recall, memory index
Notes Derwinger 2005 Methods
2 experimental groups and 1 no contact control; 5 weeks, group setting
Participants
n =20/group
Interventions
number-consonant mnemonic versus self-generated strategy training versus control group
Outcomes
free recall of digit spans
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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Derwinger 2005
(Continued)
Notes Dunlosky 2007 study 2 Methods
2x2h training sessions with pause of 2 weeks in paired associate learning for 2 groups, 1 CG; pre-post-design
Participants
n strategy/imagery training=34 n self-monitoring training=38 n control=29
Interventions
strategy/imagery vs. self-monitoring training and no contact control
Outcomes
correctly recalled word-pairs: all training groups better than control group, but significant differences between groups
Notes Dunlosky 2007 study1 Methods
2 sessions - length? 4 groups:
Participants
n strat/imag=21 n self-monit.=21 n comb=23 n control=20
Interventions
self-monitoring approach for improving older adult learning
Outcomes
correctly recalled word-pairs: no sign. differences between training groups and control
Notes Edwards 2005 Methods
5 weeks
Participants
n speed=63 n internet-training control =63
Interventions
speed of processing training
Outcomes
cognitive performance and IADL: UFOV, Road Sign Test, timed IADL, letter comparison
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Edwards 2005
Notes
(Continued)
improvements in: UFOV and transfer test for IADL, but not for cogn. factors like Stroop, Trail Making Test, letter and pattern comparison
Fabre 2002 Methods
4 groups 2 months pre-post-test
Participants
n aerobic=8 n mental=8 n combi=8 n control=8
Interventions
aerobic vs. mental training, combination and control
Outcomes
physical and cognitive variables Wechsler Memory Scale (memory ratio, paired associated learning, digit span forward, logiclal memory immediate recall, orientation, general information, mental control, visual reproductions)
Notes
control group no changes; cognitive variables improved in 3 training groups, mostly in combined group
Flynn 1990 Methods
2 treatment groups, 1 control
Participants
n manual=18 n manual+dicussion=21
Interventions
self-studied memory training manual vs. self-studied memory training manual + group discussion
Outcomes
- vocabulary subtest of Wechsler Adult Intelligence Scale-Revised - 5 memory tests: word list, word list travelling, name-face, story recall, verbal digit span forward
Notes Gratzinger 1990 Methods
baseline, after no mnemonic training, after mnemonic training
Participants
N=156, M age=68.42 MMSE>27
Interventions
- imagery + mnemonic training - relaxation + mnemonic - imagery+judgement+mnemonic
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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Gratzinger 1990
(Continued)
Outcomes
face-name recall NEO-PI
Notes
sign. overall effects but no differences between groups
Hill 1987 Methods
2 weeks group training 8x1h
Participants
n training=59 n active controls=17
Interventions
mnemonic training vs. development of own learning strategies
Outcomes
confidence ratings, name-face recall
Notes Hill 1988 Methods
6 groups; baseline, after pretraining, after mnemotraining
Participants
n imagery+ affective judgement+mnemonic=36
Interventions
imagery, relaxation, affective judgement, unspecific training
Outcomes
name-faces recall
Notes Hill 1990 Methods
Pre-/Postdesign, 4 groups; 2h+manual+homework
Participants
n mem+incentive=16 n memory=14 n active controls+incentive=16
Interventions
memory training, active controls, (incentive)
Outcomes
study time, recall time, word recall
Notes
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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Hill 1991 Methods
1 day training; 3 groups; baseline, imm. after training, 1h after training, 3 days after training
Participants
n story=23 n loci=27 n active controls=21
Interventions
narrative story, method of loci and active control condition
Outcomes
26 nouns (free recall)
Notes Levine 2007 Methods
cross-over-design
Participants
- Early training group=EG=26 - Late training group=CG=20
Interventions
goal management training as cognitive rehabilitation program
Outcomes
- simulated real life tasks (SRLT) - DEX: dysexecutive questionnaire
Notes
total score SRLT and subscore available
Mahncke 2006 Methods
1 treatment, 1 treatment control, 1 no contact control
Participants
n varies in respect to outcome measures and groups (n=50-56); age range = 60-87
Interventions
experimental computer-based training, active computer-based training in auditory language system
Outcomes
digit span, global auditory memory score
Notes Margrett 2006 Methods
6 weeks individual versus collaborative learning in inductive reasoning
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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Margrett 2006
(Continued)
Participants
n individual training=30 n partner=34 n control (questionnaire)=34
Interventions
inductive reasoning
Outcomes
letter series test word series test letter sets test
Notes Piccolini 1992 Methods
treated vs. nontreated design; 1 month
Participants
n treated=12 n non-treated=12
Interventions
mnemotechniques: visual tests, internal and external cues
Outcomes
verbal and spatial learning, short-term memory, attention, dementia scale, anxiety and depression
Notes
stratified, then randomly assigned
Rapp 2002 Methods Participants
meeting criteria for MCI (Petersen et al., 1999) including (1) a self-reported memory complaint, (2) a score on a standardized memory test at or below the 10th percentile, (3) scores on tests of all other cognitive functions greater than the 10th percentile, (4) normal global cognitive functioning, (5) no ADL or IADL deficits, and (6) the absence of dementia. Global cognitive functioning was assessed with the MMSE, perceptions of memory impairment with the Mermoy Functioning Questionnaire (MFQ), cognitive function with CERAD, perceived control over memory with the Memory Controllability Inventory and mood was administered with the Profile of Mood States n memory training=9 n control=10
Interventions
memory training on strategies, info on memory, no contact control group; 6 weeks duration (2 hours/week)
Outcomes
immediate and delayed recall of: words, shopping list, name-faces, paragraph
Notes
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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Rasmusson 1999 Methods
4 groups; pre-/post
Participants
n memory group=10 n individual memory=12 n computer=13 n wait list=11
Interventions
memory training in groups vs. individualised memory training vs. computer-based individual training vs. wait list group
Outcomes
memory: Hopkins Verbal Learning Test, Rivermead Behavioural Memory Test, Hopkins Prospective Memory Task questionnaires: Memory Controllability Inventory, Memory Functioning Questionnaire, Geriatric Depression Scale
Notes Rozzini 2007 Methods
One year longitudinal and retrospective comparison study
Participants
59 subjects affected by Mild Cognitive Impairment (MCI) according to Petersen’s criteria including Petersen et al., 2001), including: (1) memory complaint, corroborated by an informant; (2) objective memory impairment; (3) normal general cognitive functions, as determined by a clinician’s judgement based on a structured interview with the patients and an informant (Clinical Dementia Rating Scale, CDR score equal to 0.5 with memory box scores of 0.5 or 1) (Hughes et al., 1982) and a Mini Mental State Examination (MMSE) (Folstein et al., 1975) scores greater than or equal to 24; (4) no or minimal impairment in activities of daily living (Instrumental Activities of Daily Living, IADL, and Basic Activities of Daily Living, BADL) (Lawton and Brody, 1969; Katz et al., 1970) as determined by a clinical interview with the patient and an informant; and (5) non cognitive and functional impairment sufficient to meet National Institute of Neurological and Communicative Disorders and Stroke Alzheimer’s Disease and Related Disorders Association Criteria for AD (McKhann et al., 1984) , as judged by an experienced AD research clinician Depressive mood was excluded by administrating GDS-15 items.
Interventions
Fifteen subjects were randomised to receive neuropsychological training plus cholinesterase inhibitors; 22 subjects cholinesterase inhibitors alone and 22 subjects no treatment; 60 hours over 9 months (1 block = 20 hours/month with 2 month break); follow-up at 12 months
Outcomes
short story recall, letter and semantic verbal fluency, Raven matrices, Rey figure
Notes
letter verbal fluency
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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Schaffer 1992 Methods
2 treatment, 1 no contact control group
Participants
n 17/group
Interventions
learning skill group (training of attention, organisation, problem solving) vs. social support group (discussions) vs. control group
Outcomes
list recall and recognition, prose recall
Notes Scogin 1985 Methods
high complaint group vs. high complaint control; individual training
Participants
n high complaint training=20 n high complaint control=23
Interventions
92-pages manual about memory training
Outcomes
immediate and delayed recall of words, shopping list, name-faces; digit span forward, Benton visual retention test
Notes Scogin 1992 Methods
self-taught memory training vs. attention-placebo vs. wait control
Participants
n self-taught memory training=22 n attention placebo =23 n wait control=24
Interventions
self-taught memory training (117 pages manual)
Outcomes
recall of nouns, shopping list, names and faces, paragraph
Notes Stigsdotter 1989 Methods
2 weeks; pre-/post-design
Participants
n multifactor training = 9 n general activation = 9 n control = 10
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Stigsdotter 1989
(Continued)
Interventions
multifactorial training (loci, imagery, attention, relaxation) versus general cognitive activation, control group
Outcomes
- abstract and concrete word recall - digit span forward
Notes Stigsdotter 1993 study 1 Methods
8 weeks, group setting
Participants
n mulitfactor=10 n unifactor=9 n control=11
Interventions
multifactor training vs. unifactor (encoding operations), vs. control no treatment
Outcomes
abstract and concrete word recall
Notes Stigsdotter 1993 study 2 Methods
8 weeks, baseline, post-test, 6 months, 3.5 year follow-up
Participants
n multifactor training = 6 n unifactor training = 6 n control = 6
Interventions
multifactor training vs. cogn. activation (problem solving, visuospatial skills), versus control no treatment
Outcomes
total word recall, long-term retrieval
Notes Stigsdotter 1995 Methods
2 groups; group setting for 5 weeks
Participants
n multifactor=23 n control group=23
Interventions
multifactor training vs. control
Outcomes
recall of concrete and abstract words, objects and subject-performed tasks
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Stigsdotter 1995
(Continued)
Notes Valentijn 2005 Methods
8 weeks, double baseline, post-test, follow-up
Participants
analyzed n: n group=39 n individual=40 n control=38
Interventions
group mem training vs. individual training vs. wait list
Outcomes
short story immediate and delayed recall, word recall, total recall score
Notes Yesavage 1990 Methods
3 goups
Participants
n imagery=74 n relax=67 n imagery+judgement
Interventions
imagery vs. relaxaton vs. imagery + judgement training
Outcomes
word, name-face recall
Notes
Characteristics of excluded studies [ordered by study ID]
Study
Reason for exclusion
Andrewes 1996
not randomly selected: (“From those who responded to the advertisement, the first 20 women and 20 men were selected”)
Anschutz 1985
no control group
Anschutz 1987
no control group
Baldelli 1991
no control group
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(Continued)
Baltes 1988
not assigned randomly
Baltes 1989
no data (M, SD) available for baseline and post-test
Belleville 2006
not randomly assigned to treatment or control group: “to control for pre-post pracitce effects on repeated cognitive testing, a new consecutive group (...) was recruited (...).”
Best 1992
no standard deviations available
Bond 2000
stratefied patients into 3 groups with MMSE of 13-17, 18-23, 24-30, but no differentiated data for the relevant groups available
Boron 2007
assigned according to previous test performances
Brooks 1993
no data on M, SD available
Brooks 1999
age range 55-88
Calero 1997
explicitly low educated sample
Cavallini 2002
not assigned randomly, no control group
Cavallini 2003
no control group
Cerella 2006
no M, SD data available; only t-values
Cipriani 2006
no healthy control groups: MCI vs. AD vs. systsem atrophy patients
De Vreese 1998
age range 50-87; N=59, n=39 with subjective memory complaints, n=20 with objective memory complaints
Derwinger 2003
matched groups
Derwinger 2005 b
matched groups; follow-up study
Dittman-Kohli 1991
no data for cogn. performances at baseline and post-test, only data available for non-cognitive outcome variables (perceived utility and efficacy of trained tasks)
Erickson 2007
age range 55-80
Fernandez 2005
N=90, but n of the 4 subgroups unclear for baseline, post-test and follow-up. age range 59-87
Finkel 1989
not assigned randomly
Fleischmann 1985
matched groups
Gunther 2003
no control group
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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(Continued)
Hill 1989
no control group
Israel 1998
no data available on baseline and post-test means and SD
Johnston 1989
not randomly assigned
Kramer 1995
no pre-/post-test data on N, M, SD available
Labouvie-Vief 1976
no baseline data available, only data of immediate and delayed (2 weeks after training) post-test
Lachman 1992
- stratified assignment to 5 treatment conditions. - no data on subgroups n available
Martin 1998
no control group
McKitrick 1999
- no data M, SD available - age range: 55-88 years
Mohs 1998
matched groups
Neils-Strunjas 1997
no control group; multiple N interventions design
Olazarán 2004
no differentiated data on MCI
Onyper 2006
not randomly assigned
Oswald 1996
not randomized
Oswald 1998
not randomized
Oswald 2002
not randomized
Oswald 2006
not randomly assigned
Oswald 2007
not randomly assigned
Ott-Chervet 1998
MMSE>22; not specified; not randomized
Panza 1996
matched control group, no data available
Paxton 2006
assignment unclear? “either or”
Rebok 1989
no control group
Rebok 1996
only mean performances (raw scores) and change in standard scores available; no standard deviations
Rebok 1997
no data available on cognitive measures at pre-/post-test
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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(Continued)
Saczynski 1992
assigned according to previous performance
Schaie 1987
assigned according to previous performance
Schmidt 1999
fusion of no contact control group and alternative training group
Schmidt 2001
age range 45-84
Schmitt 1981
not randomly assigned
Scogin 1988
no baseline data for treatment group available 3 year follow-up data
Sheikh 1986
no standard deviations at baseline and post-test available age >55
Sitzer 2006
a review
Small 2006
Mean age of experimental and control group see chapter ’types of outcome measures’
Winningham 2003
assignment unclear “either exposed to intervention or not”
Winocur 2007
psychosocial training. no cognitive training
Wolinksy 2006 b
no cognitive outcome measure: study based on ACTIVE and investigates cognitive training and its relation to health related quality of life 5 years after baseline
Wolinsky 2006 a
no cognitive outcome measure: study based on ACTIVE and investigates cognitive training and its relation to health related quality of life 1 and 2 years after baseline
Wood 1987
matched groups
Yesavage 1983 a
no control group
Yesavage 1983 b
no M, SD values available; only F-value and significance
Yesavage 1983 c
no control group
Yesavage 1984
not randomly assigned
Zarit 1981
study 1+2: no data available on recall performances
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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DATA AND ANALYSES
Comparison 1. healthy older adults: treatment vs no contact
Outcome or subgroup title
No. of studies
No. of participants
Statistical method
1 face-name immediate recall 2 face-name delayed recall 3 visuo-spatial memory 4 short-term memory 5 paired associates 6 immediate recall 7 delayed recall
4 3 2 5 3 11 6
170 119 59 370 120 529 872
Std. Mean Difference (IV, Fixed, 95% CI) Std. Mean Difference (IV, Fixed, 95% CI) Std. Mean Difference (IV, Random, 95% CI) Std. Mean Difference (IV, Random, 95% CI) Std. Mean Difference (IV, Random, 95% CI) Std. Mean Difference (IV, Random, 95% CI) Std. Mean Difference (IV, Fixed, 95% CI)
Effect size 0.12 [-0.19, 0.43] -0.06 [-0.43, 0.30] 0.58 [-1.01, 2.17] 1.10 [-0.41, 2.61] 0.74 [-0.06, 1.54] 0.43 [0.06, 0.81] 0.39 [0.16, 0.62]
Comparison 2. healthy older adults: treatment versus active control
Outcome or subgroup title
No. of studies
No. of participants
Statistical method
1 face-name immediate recall 2 face-name delayed recall 3 visuo-spatial 4 short-term memory 5 paired associates 6 immediate recall 7 delayed recall
5 3 2 5 4 12 5
300 213 133 426 247 705 280
Std. Mean Difference (IV, Random, 95% CI) Std. Mean Difference (IV, Random, 95% CI) Std. Mean Difference (IV, Random, 95% CI) Std. Mean Difference (IV, Random, 95% CI) Std. Mean Difference (IV, Fixed, 95% CI) Std. Mean Difference (IV, Random, 95% CI) Std. Mean Difference (IV, Random, 95% CI)
Effect size 0.13 [-0.36, 0.61] -0.04 [-0.55, 0.47] -0.42 [-1.26, 0.41] 1.09 [-0.70, 2.88] -0.23 [-0.48, 0.02] 0.18 [-0.16, 0.52] 0.04 [-0.51, 0.58]
Comparison 3. MCI: treatment vs no contact
Outcome or subgroup title 1 immediate recall 2 delayed recall 3 executive function
No. of studies
No. of participants
3 2 1
72 35 37
Statistical method Std. Mean Difference (IV, Fixed, 95% CI) Std. Mean Difference (IV, Fixed, 95% CI) Std. Mean Difference (IV, Fixed, 95% CI)
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
Effect size 0.50 [0.02, 0.98] 0.69 [-0.00, 1.39] -0.09 [-0.75, 0.57]
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Comparison 4. MCI: treatment vs alternative treatment
Outcome or subgroup title
No. of studies
No. of participants
Statistical method
2 1
53 17
Std. Mean Difference (IV, Random, 95% CI) Mean Difference (IV, Fixed, 95% CI)
1 immediate recall 2 delayed recall
Effect size 1.03 [-0.14, 2.19] 3.40 [-7.52, 14.32]
HISTORY Protocol first published: Issue 4, 2006 Review first published: Issue 1, 2011
Date
Event
Description
1 September 2008
Amended
Converted to new review format.
1 August 2006
Amended
August 2006: This protocol replaces the previous protocol “Cognition-based interventions for people with Mild Cognitive Impairment” (authors Cameron MH, Clare L) and also adds a healthy population to the review’s scope
CONTRIBUTIONS OF AUTHORS MM - all correspondence, drafting of review versions, selection for trials for inclusion/exclusion, extraction of data, entry of data, interpretation of analyses LC - drafting of review versions, selection of trials for inclusion/exclusion, interpretation of data analyses MA, FZ - search for trials, obtaining copies of trial reports, selection of trials for inclusion/exclusion FZ - extraction of data, entry of data, analysis in RevMan MC - interpretation of data analyses Contact editor: Frans Verhey Consumer editors: Dave Hanbury, Victoria Morgan, Jean Town
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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DECLARATIONS OF INTEREST None known.
SOURCES OF SUPPORT Internal sources • Institute of Psychology, University of Zurich, Switzerland. • School of Psychology, University of Wales, Bangor, UK.
External sources • No sources of support supplied
DIFFERENCES BETWEEN PROTOCOL AND REVIEW Although this was considered for the analyses, there was not sufficient information to analyse follow-up data, results on transfer effects of the interventions, and conversion rates of persons with mild cognitive impairment to dementia. We increased our search range to 1970-2007 (originally 1985), and FZ joined the author group.
INDEX TERMS Medical Subject Headings (MeSH) Adaptation, Psychological; Attention; Cognition [∗ physiology]; Cognition Disorders [∗ rehabilitation]; Healthy People Programs; Memory [physiology]; Memory Disorders [∗ rehabilitation]; Randomized Controlled Trials as Topic
MeSH check words Aged; Humans; Middle Aged
Cognition-based interventions for healthy older people and people with mild cognitive impairment (Review) Copyright © 2011 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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