Updates of bioequivalence programs (including statistical power approximated by Student's t)

Updates are given of the earlier published MS-DOS programs BIOEQV37, BIOPAR37 and BIOEQNEW for the statistical analysis of bioequivalence studies. The updates are named BIOEQV52, BIOPAR40 and BIOEQNEW, respectively. Modifications and improvements in the updated programs are discussed. Calculations of statistical power for two-period crossover studies are now based on Schuirmann's two one-sided tests procedure. It is demonstrated that good approximations of power can be obtained by Student's t-statistic. This not only applies to the equations published elsewhere for the 'additive model', but also to hitherto unpublished equations for the 'multiplicative model'.