Quality of evidence

Refers to a body of evidence not to individual studies (that is, means more than risk of bias of studies). It includes consideration of risk of bias, imprecision, inconsistency, indirectness and publication bias, as well as the magnitude of treatment effect and the presence of a dose–response gradient. In the context of a systematic review, the ratings of the quality of evidence reflect the extent of our confidence that the estimates of the effect are correct. In the context of making recommendations, the quality ratings reflect the extent of our confidence that the estimates of an effect are adequate to support a particular decision or recommendation.