A class of adaptive designs

Abstract

For sequential entrance of patients in a clinical trial several adaptive designs are given by different authors from intuitive considerations. The object of such designs is to allocate the entering patients among two or more competing treatments. Here we provide a unified approach to derive a broad class of such designs through a recursion relation of the allocation probabilities of the successive entering patients. A special class of adaptive designs including the standard randomized play the winner rule is obtained from the relation. Here both the instantaneous and delayed response cases are covered

Keywords:

• urn model
• randomized play the winner rule
• delayed response