Article type
Year
Abstract
Background: Cochrane Overviews aim to provide a succinct overview of reviews relevant to a specific clinical question.
Objectives: To explore the key methods associated with producing the first Cochrane Stroke Group Overview.
Methods: Six editors from the Cochrane Stroke Group systematically explored methodological issues arising during the overview process. Monthly teleconferences and one full-day meeting were held to discuss and agree solutions to these issues. Each methodological issue, and how it was addressed, was recorded.
Results: Our completed overview included 40 reviews (19 Cochrane, 21 non-Cochrane). Key methodological challenges encountered related to:
1. inclusion of non-Cochrane reviews: this added substantial complexity to review inclusion, primarily due to overlap between reviews, requiring systematic exploration of the inclusion of more than 700 studies; 37 reviews were excluded as they were superseded by more up-to-date or comprehensive reviews;
2. quality assessment of included reviews: we found use of the AMSTAR quality assessment tool challenging due to its use of many multifaceted questions. We developed a modified version of the AMSTAR tool (mAMSTAR), comprising 30 simple uni-variable questions. This enabled transparent documentation of the process of quality assessment.
3. quality of evidence within reviews: we planned to use the GRADE approach to assign levels of evidence to each of the 127 relevant comparisons included in the overview, but found it difficult to achieve consistent application. We therefore developed and used an objective algorithm based on participant numbers, trial risk of bias, heterogeneity and review quality.
4. strength of implications: only 1/127 comparisons was graded as high quality, and 76/127 comparisons were graded as low or very-low quality evidence, limiting clinical implications.
Conclusions: Overviews should benefit evidence-based stroke care, but tools used to support Cochrane Overviews need further methodological development. Our Overview comprehensively, rigorously and effectively signposts clinicians to reviews that are most likely to support delivery of effective care.
Objectives: To explore the key methods associated with producing the first Cochrane Stroke Group Overview.
Methods: Six editors from the Cochrane Stroke Group systematically explored methodological issues arising during the overview process. Monthly teleconferences and one full-day meeting were held to discuss and agree solutions to these issues. Each methodological issue, and how it was addressed, was recorded.
Results: Our completed overview included 40 reviews (19 Cochrane, 21 non-Cochrane). Key methodological challenges encountered related to:
1. inclusion of non-Cochrane reviews: this added substantial complexity to review inclusion, primarily due to overlap between reviews, requiring systematic exploration of the inclusion of more than 700 studies; 37 reviews were excluded as they were superseded by more up-to-date or comprehensive reviews;
2. quality assessment of included reviews: we found use of the AMSTAR quality assessment tool challenging due to its use of many multifaceted questions. We developed a modified version of the AMSTAR tool (mAMSTAR), comprising 30 simple uni-variable questions. This enabled transparent documentation of the process of quality assessment.
3. quality of evidence within reviews: we planned to use the GRADE approach to assign levels of evidence to each of the 127 relevant comparisons included in the overview, but found it difficult to achieve consistent application. We therefore developed and used an objective algorithm based on participant numbers, trial risk of bias, heterogeneity and review quality.
4. strength of implications: only 1/127 comparisons was graded as high quality, and 76/127 comparisons were graded as low or very-low quality evidence, limiting clinical implications.
Conclusions: Overviews should benefit evidence-based stroke care, but tools used to support Cochrane Overviews need further methodological development. Our Overview comprehensively, rigorously and effectively signposts clinicians to reviews that are most likely to support delivery of effective care.