Analysis of Clinical Trials Using SAS

4.3 Stochastic Curtailment Tests

We have pointed out repeatedly throughout the chapter that pivotal clinical trials are routinely monitored to find early evidence of beneficial or harmful effects. Section 4.2 introduced an approach to the design and analysis of group sequential trials based on repeated significance testing. This section looks at sequential testing procedures used in a slightly different context. Specifically, it reviews recent advances in the area of stochastic curtailment with emphasis on procedures for futility monitoring.

To help understand the difference between repeated significance and stochastic curtailment tests, recall that repeated significance testing is centered around the notion of error spending. The chosen error ...