A new statistical procedure for testing equivalence in two-group comparative bioavailability trials.

The clinical problem of testing for equivalence in comparative bioavailability trials is restated in terms of the proper statistical hypotheses. A simple t-test procedure for these hypotheses has been developed that is more powerful than the methods based on usual (shortest) and symmetric confidence intervals. In this note, this new procedure is explained and an example is given, including the method for sample size determination.