Guest edited by Professor David Torgerson this new series reviews previous stepped wedge studies, explores key issues of design and forms a comprehensive overview of the current state of knowledge of the design.
There is often a tension between policy makers wishing to implement a novel intervention and researchers wanting time to do a controlled evaluation. One trial design that can address this tension is the stepped wedged randomised trial. In a stepped wedge trial, all groups or clusters of participants eventually receive the intervention, but the implementation is staggered in a random fashion allowing a robust evaluation to take place. Recently there has been an upsurge in interest in the design, which is not yet well understood. This series of papers reviews previous stepped wedge studies and explores key issues of design, forming a comprehensive overview of the current state of knowledge of the design.