Multiple Testing to Establish Noninferiority of k Treatments with a Reference Based on the Ratio of Two Means

Abstract

It is the aim of most active control trials to show that the treatment(s) under investigation is (are) not inferior to the reference by more than a prespecified clinically irrelevant amount. In the situation of a multiarmed trial with more than one test treatment it may be required that noninferiority of all these groups to the reference be demonstrated. Alternatively, it may by sufficient to prove noninferiority of at least one of the test treatments to the reference. These clinical questions correspond to the concepts of global and partial noninferiority. For both scenarios test procedures are given for the situation that the noninferiority margin is expressed as a proportion of the unknown reference mean.