Recommendations by Cochrane Review Groups for assessment of the risk of bias in studies

Andreas Lundh, Peter C Gøtzsche

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Resumé

BACKGROUND: Assessing the risk of bias in individual studies in a systematic review can be done using individual components or by summarizing the study quality in an overall score.

METHODS: We examined the instructions to authors of the 50 Cochrane Review Groups that focus on clinical interventions for recommendations on methodological quality assessment of studies.

RESULTS: Forty-one of the review groups (82%) recommended quality assessment using components and nine using a scale. All groups recommending components recommended to assess concealment of allocation, compared to only two of the groups recommending scales (P < 0.0001). Thirty-five groups (70%) recommended assessment of sequence generation and 21 groups (42%) recommended assessment of intention-to-treat analysis. Only 28 groups (56%) had specific recommendations for using the quality assessment of studies analytically in reviews, with sensitivity analysis, quality as an inclusion threshold and subgroup analysis being the most commonly recommended methods. The scales recommended had problems in the individual items and some of the groups recommending components recommended items not related to bias in their quality assessment.

CONCLUSION: We found that recommendations by some groups were not based on empirical evidence and many groups had no recommendations on how to use the quality assessment in reviews. We suggest that all Cochrane Review Groups refer to the Cochrane Handbook for Systematic Reviews of Interventions, which is evidence-based, in their instructions to authors and that their own guidelines are kept to a minimum and describe only how methodological topics that are specific to their fields should be handled.

OriginalsprogEngelsk
TidsskriftB M C Medical Research Methodology
Vol/bind8
Sider (fra-til)22
ISSN1471-2288
DOI
StatusUdgivet - 21. apr. 2008

Fingeraftryk

Intention to Treat Analysis
Focus Groups
Guidelines

Citer dette

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abstract = "BACKGROUND: Assessing the risk of bias in individual studies in a systematic review can be done using individual components or by summarizing the study quality in an overall score.METHODS: We examined the instructions to authors of the 50 Cochrane Review Groups that focus on clinical interventions for recommendations on methodological quality assessment of studies.RESULTS: Forty-one of the review groups (82{\%}) recommended quality assessment using components and nine using a scale. All groups recommending components recommended to assess concealment of allocation, compared to only two of the groups recommending scales (P < 0.0001). Thirty-five groups (70{\%}) recommended assessment of sequence generation and 21 groups (42{\%}) recommended assessment of intention-to-treat analysis. Only 28 groups (56{\%}) had specific recommendations for using the quality assessment of studies analytically in reviews, with sensitivity analysis, quality as an inclusion threshold and subgroup analysis being the most commonly recommended methods. The scales recommended had problems in the individual items and some of the groups recommending components recommended items not related to bias in their quality assessment.CONCLUSION: We found that recommendations by some groups were not based on empirical evidence and many groups had no recommendations on how to use the quality assessment in reviews. We suggest that all Cochrane Review Groups refer to the Cochrane Handbook for Systematic Reviews of Interventions, which is evidence-based, in their instructions to authors and that their own guidelines are kept to a minimum and describe only how methodological topics that are specific to their fields should be handled.",
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Recommendations by Cochrane Review Groups for assessment of the risk of bias in studies. / Lundh, Andreas; Gøtzsche, Peter C.

I: B M C Medical Research Methodology, Bind 8, 21.04.2008, s. 22.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

TY - JOUR

T1 - Recommendations by Cochrane Review Groups for assessment of the risk of bias in studies

AU - Lundh, Andreas

AU - Gøtzsche, Peter C

PY - 2008/4/21

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N2 - BACKGROUND: Assessing the risk of bias in individual studies in a systematic review can be done using individual components or by summarizing the study quality in an overall score.METHODS: We examined the instructions to authors of the 50 Cochrane Review Groups that focus on clinical interventions for recommendations on methodological quality assessment of studies.RESULTS: Forty-one of the review groups (82%) recommended quality assessment using components and nine using a scale. All groups recommending components recommended to assess concealment of allocation, compared to only two of the groups recommending scales (P < 0.0001). Thirty-five groups (70%) recommended assessment of sequence generation and 21 groups (42%) recommended assessment of intention-to-treat analysis. Only 28 groups (56%) had specific recommendations for using the quality assessment of studies analytically in reviews, with sensitivity analysis, quality as an inclusion threshold and subgroup analysis being the most commonly recommended methods. The scales recommended had problems in the individual items and some of the groups recommending components recommended items not related to bias in their quality assessment.CONCLUSION: We found that recommendations by some groups were not based on empirical evidence and many groups had no recommendations on how to use the quality assessment in reviews. We suggest that all Cochrane Review Groups refer to the Cochrane Handbook for Systematic Reviews of Interventions, which is evidence-based, in their instructions to authors and that their own guidelines are kept to a minimum and describe only how methodological topics that are specific to their fields should be handled.

AB - BACKGROUND: Assessing the risk of bias in individual studies in a systematic review can be done using individual components or by summarizing the study quality in an overall score.METHODS: We examined the instructions to authors of the 50 Cochrane Review Groups that focus on clinical interventions for recommendations on methodological quality assessment of studies.RESULTS: Forty-one of the review groups (82%) recommended quality assessment using components and nine using a scale. All groups recommending components recommended to assess concealment of allocation, compared to only two of the groups recommending scales (P < 0.0001). Thirty-five groups (70%) recommended assessment of sequence generation and 21 groups (42%) recommended assessment of intention-to-treat analysis. Only 28 groups (56%) had specific recommendations for using the quality assessment of studies analytically in reviews, with sensitivity analysis, quality as an inclusion threshold and subgroup analysis being the most commonly recommended methods. The scales recommended had problems in the individual items and some of the groups recommending components recommended items not related to bias in their quality assessment.CONCLUSION: We found that recommendations by some groups were not based on empirical evidence and many groups had no recommendations on how to use the quality assessment in reviews. We suggest that all Cochrane Review Groups refer to the Cochrane Handbook for Systematic Reviews of Interventions, which is evidence-based, in their instructions to authors and that their own guidelines are kept to a minimum and describe only how methodological topics that are specific to their fields should be handled.

KW - Advisory Committees

KW - Bias

KW - Clinical Trials as Topic

KW - Evidence-Based Medicine

KW - Meta-Analysis as Topic

KW - Quality Control

KW - Reproducibility of Results

KW - Research Design

KW - Review Literature as Topic

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1186/1471-2288-8-22

DO - 10.1186/1471-2288-8-22

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VL - 8

SP - 22

JO - B M C Medical Research Methodology

JF - B M C Medical Research Methodology

SN - 1471-2288

ER -