Simultaneous identifications of the minimum effective dose in each of several groups

Abstract

One primary goal in dose-response studies for drug development is to identify the minimum effective dose (MED) which is the lowest dose level with an effect that exceeds that of the zero dose control. In this paper, we consider step-down closed testing procedures on the basis of pairwise and Helmert contrasts suggested by Tamhane et al. [ Tamhane, A. C., Hochberg, Y., and Dunnett, C. W., 1996, Multiple test procedures for dose finding. Biometrics, 52, 21 - 37.] for the situation where one wishes to make all such MED identifications simultaneously in each of several groups. An example is given to illustrate the proposed tests. The Monte Carlo studies are further implemented to compare the relative error rate and power performances of the proposed tests.