Identifying the ‘incredible’! Part 1: assessing the risk of bias in outcomes included in systematic reviews

In this editorial, we introduced risk of bias as the perceived risk that the results of a research study may underestimate or overestimate the truth. Systematic review authors should perform a domain-based risk of bias assessment that reflects risk of bias instead of assessing study quality. If a research study reports multiple outcome measures, separate risk of bias assessments should be performed for each outcome measure.