Assessing individual bioequivalence using the structural equation model.

The structural equation model (SEM) is introduced as a useful approach for assessing individual bio-equivalence. SEM parameters are estimated using a partial likelihood analysis and the hypotheses of individual bioequivalence is evaluated in a disaggregate way, testing separately the hypothesis concerning SEM parameters, and assessing the overall hypothesis of individual bioequivalence using the intersection-union principle. Limits of bioequivalence for SEM parameters are proposed and a power analysis is carried out. Copyright 2003 John Wiley & Sons, Ltd.