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The Cochrane Collaboration's tool for assessing risk of bias in randomised trials

Julian P. T. Higgins, Doug G. Altman, Peter Christian Gøtzsche, Peter Jüni, David Moher, Andrew David Oxman, Jelena Savović, Kenneth F. Schulz et al.

BMJ, 2011

34,904 citations

Abstract

Flaws in the design, conduct, analysis, and reporting of randomised trials can cause the effect of an intervention to be underestimated or overestimated. The Cochrane Collaboration’s tool for assessing risk of bias aims to make the process clearer and more accurate

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Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 2 of 5 (High · randomized trial). Randomized trials of a reasonable size are the strongest single-study design.

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