Stepped wedge design is a special group randomized controlled trial

and its main feature is phased implementation of intervention without setting specific controlled group. This methodology could achieve parallel randomized controlling

and also avoid ethical problems. In the recent decade

this design method is attracting researchers’ concern

and the relative theory is becoming complete. This article introduces the key points in designing

implementing and statistical analysis

and proposes the stepped wedge design which could be used in Chinese medicine treating and managing chronic diseases

including acquired immune deficiency syndrome

tuberculosis

and hepatitis.