A Note on Missing Data in Noninferiority Trials

Two important topics associated with the design and analysis of clinical trials, missing data and noninferiority, are currently receiving much consideration in the literature, in scientific forums, and in health authority interactions. As methods and practices for these topics are evolving, understandably most of the discussion and guidance have focused on them individually. However, in considering how best to address these two issues from a standpoint of design or analysis within a particular trial in which both are relevant, it is helpful to consider them jointly. For example, how one develops an analysis plan to accommodate missing data in a noninferiority study may, or may not, be identical to the approach for a superiority trial. Here we describe how these issues might interact in a given trial; that is, we raise some specific points relevant to both of these topics that may be particularly important to consider when both issues are present in the same trial.