Cognitive remediation in schizophrenia: A methodological appraisal of systematic reviews and meta-analyses

doi:10.1016/j.jpsychires.2016.01.004

Journal of Psychiatric Research

Volume 75, April 2016, Pages 91-106

https://doi.org/10.1016/j.jpsychires.2016.01.004 Get rights and content

Abstract

Objective

Systematic reviews and meta-analyses are a primary source of evidence when evaluating the benefit(s) of cognitive remediation (CR) in schizophrenia. These studies are designed to rigorously synthesize scientific literature; however, cannot be assumed to be of high methodological quality. The aims of this report were to: 1) review the use of systematic reviews and meta-analyses regarding CR in schizophrenia; 2) conduct a systematic methodological appraisal of published reports examining the benefits of this intervention on core outcome domains; and 3) compare the correspondence between methodological and reporting quality.

Method

Electronic databases were searched for relevant articles. Twenty-one reviews met inclusion criteria and were scored according to the AMSTAR checklist-a validated scale of methodological quality. Five meta-analyses were also scored according to PRISMA statement to compare ‘quality of conduct’ with ‘quality of reporting’.

Results

Most systematic reviews and meta-analyses shared strengths and fell within a ‘medium’ level of methodological quality. Nevertheless, there were consistent areas of potential weakness that were not addressed by most reviews. These included the lack of protocol registration, uncertainty regarding independent data extraction and consensus procedures, and the minimal assessment of publication bias. Moreover, quality of conduct may not necessarily parallel quality of reporting, suggesting that consideration of these methods independently may be important.

Conclusions

Reviews concerning CR for schizophrenia are a valuable source of evidence. However, the methodological quality of these reports may require additional consideration. Enhancing quality of conduct is essential for enabling research literature to be interpreted with confidence.

Section snippets

Cognitive remediation in schizophrenia

Cognitive remediation (CR) represents a broad range of learning-based interventions that aim to achieve improvements in cognition and/or the self-management of these abilities (Saperstein and Kurtz, 2013). The ultimate goal of CR is generalization to untrained cognitive skills as well as transfer to real-world psychosocial outcomes (Saperstein and Kurtz, 2013). CR may involve exposure to repetative training exercises (i.e. “drill-and-practice”), strategic discussions about how to manage

Objective

The primary aims of this study were to: 1) review the use of systematic reviews and meta-analyses concerning CR in schizophrenia; and 2) conduct a systematic methodological appraisal of published systematic reviews and meta-analyses that have examined the efficacy (or effectiveness) of this intervention on core outcome domains in schizophrenia using the AMSTAR checklist. It was intended that this would provide direction regarding ways to enhance the quality of future reviews of CR for

Search strategy

The reporting standards and methodological rigor of this report was informed by the PRISMA statement and AMSTAR checklist respectively, where appropriate. A search of systematic review and meta-analysis protocol registries including PROSPERO, the Cochrane Database of Systematic Reviews, and Joanna Briggs Institute Library revealed that no similar studies were underway as of December 2014.

Article searches were conducted using multiple electronic databases including PsychINFO (1806–2015),

Search results

The initial electronic search revealed 361 records; however, only 189 remained after duplicates were removed (n = 172). After title and abstract screening, 24 articles proceeded to full-text review. Seven additional reports were identified after scanning each title in the reference list of these articles. All but two of these additional reports (Bellack, 2004, Rund and Borg, 1999) met the inclusion criteria after abstract screening. Therefore, overall, a total of 29 articles proceeded to

Discussion

The primary aims of this report were to review the use of systematic reviews and meta-analyses concerning CR in schizophrenia, and systematically evaluate the methodological quality of published reviews using the AMSTAR checklist. It was intended that highlighting areas of strength and weakness would help inform future reviews in this area. To our knowledge, this was the first methodological evaluation of reviews in this field. A secondary aim was to compare total scores on the AMSTAR checklist

Role of funding source

We did not receive funding to prepare or produce this article.

Conflicts of interest

We declare that all contributing authors do not have any competing interests or conflicts of interest.

Statement of contribution

All named authors had a key role in the preparation of this manuscript, as briefly described below.

Bryce – Mr Bryce wrote and prepared the majority of the manuscript was heavily involved in developing the concept of this review, and was the first independent reviewer.

Sloan – Ms Sloan was the second independent reviewer of articles.

Lee – Dr Lee mediated the consensus procedure for the review and was involved in editing the manuscript.

Ponsford – Prof Ponsford was involved in concept formation and

Acknowledgments

We thank the authors from each of the articles reviewed for their contribution to the field.

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Review articleCognitive remediation in schizophrenia: A methodological appraisal of systematic reviews and meta-analyses

Abstract

Objective

Method

Results

Conclusions

Section snippets

Cognitive remediation in schizophrenia

Objective

Search strategy

Search results

Discussion

Role of funding source

Conflicts of interest

Statement of contribution

Acknowledgments

J. Psychiatr. Res.

Neurosci. Biobehav. Rev.

World Psychiatry

J. Psychiatr. Res.

The Lancet

Neuropsychologia

Aust. N. Z. J. Public Health

The Lancet

Control. Clin. Trials

Schizophr. Res.

J. Clin. Epidemiol.

J. Clin. Epidemiol.

Psychiatry Res.

Quality of conduct and reporting of meta-analyses of surgical interventions

Ann. Surg.

Exploring the quality of systematic reviews on pharmacist interventions in patients with diabetes: an overview

Ann. Pharmacother.

Psychosocial interventions for very early and early-onset schizophrenia: a review of treatment efficacy

Curr. Opin. Psychiatry

Cognitive remediation in the early course of schizophrenia: a critical review

Curr. Pharm. Des.

Cognitive remediation in schizophrenia: current status and future perspectives

Schizophr. Res. Treat.

Skills training for people with severe mental illness

Psychiatr. Rehabil. J.

Where to fo Australian mental health services? promoting self efficacy

Aust. N. Z. J. Psychiatry

Cognitive Remediation for Negative Symptoms in Schizophrenia: a Network Meta-analysis. PROSPERO

Current approaches to treatments for schizophrenia spectrum disorders, part II: psychosocial interventions and patient-focused perspectives in psychiatric care

J. Neuropsychiatr. Dis. Treat.

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The importance of PROSPERO to the National Institute for Health Research

Syst. Rev.

The quality of reports of critical care meta-analyses in the cochrane database of systematic reviews: an independent appraisal

Crit. Care Med.

Publication bias in the social sciences: unlocking the file drawer

Science

Neurocognitive deficits and functional outcome in schizophrenia: are we measuring the right stuff?

Schizophr. Bull.

Efficacy and specificity of computer-assisted cognitive remediation in schizophrenia: a meta-analytical study

Psychol. Med.

Cognitive rehabilitation for people with schizophrenia and related conditions

Cochrane Database Syst. Rev.

Social cognition training for individuals with schizophrenia: emerging evidence

Am. J. Psychiatr. Rehabil.

Neurocognitive effects of antipsychotic medications in patients with chronic schizophrenia in the CATIE trial

Arch. General Psychiatry

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Psychopharmacology

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Open Dent. J.

Review article
Cognitive remediation in schizophrenia: A methodological appraisal of systematic reviews and meta-analyses