[General contemplation on causality in appraising clinical efficacy of traditional Chinese medicine].

This paper briefly introduced the general principles for causality in scientific researches and clinical studies, addressed the importance of population-based approaches in it, and also reviewed the developing course and presented the elementary requirements of randomized controlled trials (RCTs). The author identified with views that as compared with the research design of other types, RCTs is the most authentic one in the aspect of causality of efficacy and intervention. It is stressed that a causal inference for the efficacy assessment of traditional Chinese medicine (TCM) must meet the nomothetic criteria. The author emphasized that the scientific merits of RCTs are not only for assessing the efficacy of conventional treatments, but also for TCM intervention owing to RCTs yield stronger inferences about therapeutic intervention than other study designs, which are wildly accepted by academic communities.