Nonparametric Identification of the Minimum Effective Dose for Randomized Block Designs

One primary purpose in a dose–response study for drug development is to identify the minimum effective dose (MED), which is the lowest dose level producing an effect over that of the zero-dose control. Proposed herein is a nonparametric step-down closed testing procedure for identifying the MED in a randomized block design with one or more observations per cell. The associated p-value of the identified MED is then obtained. Numerical examples further demonstrate the feasibility of the proposed testing procedure. Finally, the comparative results of a Monte Carlo investigation of the relative error rate and power performances are presented and discussed.