Bioequivalence and Bioavailability Forum

❝ Here you err!

❝ To account for period effects you have to apply the Wilcoxon–Mann–Whitney test with sequence as grouping factor if you evaluate a 2x2 cross-over design. This test is sometimes also called Hauschke test. Guess why .

• Unlike the nonparametric confidence interval according to Steinijans and Diletti [1983], the non­parametric approach by Hauschke et al. [1990] is no longer limited by the assumption of equal period effects. Although, according to our vast experience, unequal period effects are extremely rare, they may result in a biased point estimate and an unnecessarily wide confidence interval if the procedure assuming equal period effects is applied incorrectly. To avoid this, the nonparametric procedure by Steinijans and Diletti [1983] should generally be replaced by that of Hauschke et al. [1990].

• Steinijans VW, Hauschke D. Update on the statistical analysis of bioequivalence studies. Int J Clin Pharm Ther Toxicol. 1990;28(3):105–10. PMID 2318545.
  Int J Clin Pharmacol Ther Toxicol. 1992;30(Suppl 1):S45-50. PMID 1601531.