Abstract
A fuzzy tolerable difference may be introduced in the statistical analysis for equivalence of response rate of test drug (T) with respect to that of standard drug (S) by formulating a membership function. When the membership function is expressed as a step function which indicates the degree of reluctance of accepting a seemingly less effective but much less toxic or more useful T, the procedure is not so complicated. This paper describes the application of this fuzzy equivalence with step function to the results of a double-masked randomized controlled trial in which the efficacy of intravenous drip of dopamine (S) and that of oral administration of docarpamine (T, TA-870) were compared in patients with circulatory failure.
