A note on sample size determination for bioequivalence studies with high-order crossover designs.
Similar to Liu and Chow, approximate formulas for sample size determination are derived based on Schuirmann's two one-sided tests procedure for bioequivalence studies for the additive and the multiplicative models under various higher order crossover designs for comparing two formulations of a drug product. The higher order crossover designs under study include Balaam's design, the two-sequence dual design, and two four-period designs (with two and four sequences), which are commonly used for assessment of bioequivalence between formulations. The derived formulas are simple enough to be carried out with a pocket calculator. The number of subjects required for each of the four higher order designs are tabulated for selected powers and various parameter values.
Department of Medical Affairs, Pasteur Mérieux Connaught, Swiftwater, Pennsylvania 18370, USA.
K W
KW
Chen
S C
SC
Chow
G
G
Li
D002986:Clinical Trials as Topic; D018592:Cross-Over Studies; D006801:Humans; D018401:Sample Size; D013810:Therapeutic Equivalency