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**Asymptotic properties of adaptive designs for clinical trials with delayed response.**
*(English)*
Zbl 1012.62087

Summary: 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.

### MSC:

62L05 | Sequential statistical design |

62P10 | Applications of statistics to biology and medical sciences; meta analysis |

62F12 | Asymptotic properties of parametric estimators |

### References:

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[20] | 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 |

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