Which Randomized Controlled Trials Can Be Taken as Evidence?

Abstract

Randomized controlled studies（RCTs）offer the most reliable information to evidence-based medicine. Nevertheless, some studies use inappropriate methods or reach misleading conclusions. There are several items to check by which we can relatively easily judge whether a randomized controlled study provides evidence of high or low reliability. Studies whose hypotheses are unclear, which lack clearly defined aims, whose primary outcome measures do not match the study aim, whose conclusions are drawn from secondary outcome measures, or which show significant differences that are not clinically meaningful, should not be regarded as providing highly reliable evidence. In this review, I describe eight simple items by which one can judge whether or not the results of a randomized controlled study can be used for evidence-based medicine.