### Asymptotic Properties of Adaptive designs for Clinical Trials with delayed Response

Z.D. Bai, Feifang Hu, and William F. Rosenberger
Source: Ann. Statist. Volume 30, Number 1 (2002), 122-139.

#### Abstract

For adaptive clinical trials using a generalized Friedman’s urn design, we derive the limiting distribution of the urn composition under staggered entry and delayed response. The stochastic delay mechanism is assumed to depend on both the treatment assigned and the patient’s response. A very general setup is employed with $K$ treatments and $L$ responses. When $L = K =2$, one example of a generalized Friedman’s urn design is the randomized play-the-winner rule. An application of this rule occurred in a clinical trial of depression, which had staggered entry and delayed response. We show that maximum likelihood estimators from such a trial have the usual asymptotic properties.

First Page:
Primary Subjects: 62G10
Full-text: Open access

Permanent link to this document: http://projecteuclid.org/euclid.aos/1015362187
Digital Object Identifier: doi:10.1214/aos/1015362187
Mathematical Reviews number (MathSciNet): MR1892658
Zentralblatt MATH identifier: 1012.62087

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CHARLOTTESVILLE, VIRGINIA 22904-4135 E-MAIL: fh6e@pitman.stat.virginia.edu W. F. ROSENBERGER DEPARTMENT OF MATHEMATICS AND STATISTICS
UNIVERSITY OF MARYLAND, BALTIMORE COUNTY 1000 HILLTOP CIRCLE
BALTIMORE, MARYLAND 21250