Introduction to the Special Issue. Randomized Controlled Trials (RCTs) in Clinical and Community Settings: Challenges, Alternatives, and Supplementary Designs.

This article provides an overview of the contributions to the special issue on Randomized Controlled Trials (RCTs) in Clinical and Community Settings: Challenges, Alternatives, and Supplementary Designs. The article introduces the challenges of conducting RCTs in dynamic real-world settings and outlines the need to consider alternative and supplementary designs.