Assessment of Safety

Abstract

In most clinical trials in phase II and III, the primary endpoint measures efficacy and therefore sample size calculation is based on this outcome. However, there are also situations were the primary objective concerns safety. Furthermore, even if sample size calculation is based on an efficacy endpoint, one is commonly interested which extent of information can be gained on safety aspects with the number of patients included in the study. In this chapter, a binary endpoint measuring an undesirable event, such as an adverse event, is considered. Three approaches to the analysis of such outcomes and related methods for sample size or power calculation are presented: testing hypotheses on the event probability, estimating the event probability with specified precision, and observing at least one event with specified probability.