Article type
Year
Abstract
Background: Individual Patient Data (IPD) meta-analyses have been described as the 'gold standard'. However, they are still relatively uncommon within the Cochrane Library and there may be increased potential to improve the findings of traditional meta-analyses by including IPD. Furthermore, traditional reviews may be a useful vehicle for highlighting the added value of IPD for future research.
Objectives: To assess the current use, and potential for use of IPD in current Cochrane Reviews produced by the Cochrane Pregnancy and Childbirth Group.
Methods: A random sample of 100 of the reviews available on the Cochrane Pregnancy and Childbirth website were downloaded. Various aspects of the reviews were recorded including number of included studies, number of comparisons, risks of bias in included studies and number of heterogeneous comparisons. Any reference to current or future use of IPD was recorded, as well as planned and executed subgroup analyses. A recommendation for whether IPD would be valuable was given based on characteristics of the reviews.
Results: Ninety of the 100 reviews included at least one study and 10 were empty. IPD was likely or possibly in use in 11 of the 90 non-empty reviews, however the methods were not well discussed. Seeking IPD was recommended for 64 of the non-empty reviews, and recommended subject to advice from a clinician in a further seven reviews. Common reasons for recommending that a review should seek IPD included presence of heterogeneity that could be explored with IPD to overcome potential bias due to selective reporting or incomplete outcome data, and to overcome insufficient data to complete all planned analyses.
Conclusions: Our investigation indicates that few Cochrane Pregnancy and Childbirth reviews currently include IPD, but there is potential to overcome, or at least minimise important issues, by including IPD. However, from a clinical perspective it may not always be justified to seek IPD, as the traditional approach using aggregate data may be sufficient to answer the research questions, and more resources, time and statistical expertise are required for IPD meta-analyses.
Objectives: To assess the current use, and potential for use of IPD in current Cochrane Reviews produced by the Cochrane Pregnancy and Childbirth Group.
Methods: A random sample of 100 of the reviews available on the Cochrane Pregnancy and Childbirth website were downloaded. Various aspects of the reviews were recorded including number of included studies, number of comparisons, risks of bias in included studies and number of heterogeneous comparisons. Any reference to current or future use of IPD was recorded, as well as planned and executed subgroup analyses. A recommendation for whether IPD would be valuable was given based on characteristics of the reviews.
Results: Ninety of the 100 reviews included at least one study and 10 were empty. IPD was likely or possibly in use in 11 of the 90 non-empty reviews, however the methods were not well discussed. Seeking IPD was recommended for 64 of the non-empty reviews, and recommended subject to advice from a clinician in a further seven reviews. Common reasons for recommending that a review should seek IPD included presence of heterogeneity that could be explored with IPD to overcome potential bias due to selective reporting or incomplete outcome data, and to overcome insufficient data to complete all planned analyses.
Conclusions: Our investigation indicates that few Cochrane Pregnancy and Childbirth reviews currently include IPD, but there is potential to overcome, or at least minimise important issues, by including IPD. However, from a clinical perspective it may not always be justified to seek IPD, as the traditional approach using aggregate data may be sufficient to answer the research questions, and more resources, time and statistical expertise are required for IPD meta-analyses.