Modern Approaches to Clinical Trials Using SAS: Classical, Adaptive, and Bayesian Methods

2.1 Introduction

One of the major advances in modern clinical trials is the invention and application of sequential analysis in experimental design. This type of design is often called the group sequential design. A group sequential design consists of multiple stages and employs a repeated significance testing strategy. It is one of the most commonly used adaptive designs. The Encyclopaedic Companion to Medical Statistics [1] defines sequential analysis as “a method allowing hypothesis tests to be conducted on a number of occasions as data accumulate through the course of a trial. A trial monitored in this way is usually called a sequential trial.” For example, in a phase III randomized clinical trial that has several stages; an interim analysis ...