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PubMed1992

Sample size for a dose-response study.

This paper deals with a method of sample size allocation for a dose-response study assuming a logistic model for the dose-response curve. The method is based on the precision with which one wishes to estimate the dose that would produce the efficacy resulting in a clinically important difference from a placebo. An example is given to illustrate the methodology. The main development of the paper is for a binary response and is suitably modified for a continuous variable.

Dose-Response Relationship, Drug↗

PubMed1991

Comparison of treatments in a combination therapy trial.

Although the min test proposed by Laska and Meisner (1) for testing superiority of a combination to each of its components is the uniformly most powerful monotone test, it is conservative in the neighborhood of origin. Considering a restricted null hypothesis, we analyze a general linear model. The p value associated with the proposed test and a confidence interval for the shortest distance between the combination therapy and component therapies are computed. Analysis of a design with two or more combinations is proposed. A numerical example is given and a problem of optimal allocation of the sample sizes and other relevant design issues are discussed.

Confidence Intervals↗