Group sequential, sample size re-estimation and two-stage adaptive designs in clinical trials: A comparison

摘要

Recently there have been quite a few enthusiastic discussions on the topic about adaptive designs for clinical trials . Controversies have been generated among authors who favour versus those who do not quite favour adaptive designs (AD). Some of the controversies have involved group sequential (GS) designs, sample size re-estimation (SSR) procedures, and their variants and mixtures. In this commentary I would like to offer some comparisons with respect to the distinct purposes and key operating aspects of these types of designs