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. 2018 Sep 28:362:k3802.
doi: 10.1136/bmj.k3802.

Outcome reporting bias in trials: a methodological approach for assessment and adjustment in systematic reviews

Jamie J Kirkham  1 , Douglas G Altman  2 , An-Wen Chan  3 , Carrol Gamble  4 , Kerry M Dwan  5 , Paula R Williamson  4
Affiliations

Outcome reporting bias in trials: a methodological approach for assessment and adjustment in systematic reviews

Jamie J Kirkham et al. BMJ. .

Abstract

Systematic reviews of clinical trials aim to include all relevant studies conducted on a particular topic and to provide an unbiased summary of their results, producing the best evidence about the benefits and harms of medical treatments. Relevant studies, however, may not provide the results for all measured outcomes or may selectively report only some of the analyses undertaken, leading to unnecessary waste in the production and reporting of research, and potentially biasing the conclusions to systematic reviews. In this article, Kirkham and colleagues provide a methodological approach, with an example of how to identify missing outcome data and how to assess and adjust for outcome reporting bias in systematic reviews.

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Conflict of interest statement

Competing interests: All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf and declare: no financial relationships with any organisations that might have an interest in the submitted work in the previous three years. DGA, KMD, CG, JJK, and PRW would like to declare their involvement in the ORBIT (Outcome Reporting Bias in Trials) research programme, which is frequently referred to in this article.

Figures

Fig 1
Fig 1
Outcome matrix for review on topiramate add-on use for drug resistant partial epilepsy, with letters indicating ORBIT (Outcome Reporting Bias In Trials) classifications
See this image and copyright information in PMC

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