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Journal ArticleDOI

67A Designed extension of studies based on conditional power

Michael A. Proschan, +1 more
- 01 Jun 1995 - 
- Vol. 16, Iss: 3
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TLDR
A flexible method of extending a study based on conditional power, where the significance of the treatment difference at the planned end is used to determine the number of additional observations needed and the critical value necessary after accruing those additional observations.
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This article is published in Controlled Clinical Trials.The article was published on 1995-06-01. It has received 252 citations till now. The article focuses on the topics: Extension (predicate logic).

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Citations
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Journal ArticleDOI

Adaptive sample size calculations in group sequential trials.

TL;DR: A method for group sequential trials that is based on the inverse normal method for combining the results of the separate stages is proposed, which enables data-driven sample size reassessments during the course of the study.
Journal ArticleDOI

Modification of Sample Size in Group Sequential Clinical Trials

TL;DR: A new group sequential test procedure is developed by modifying the weights used in the traditional repeated significance two-sample mean test, which has the type I error probability preserved at the target level and can provide a substantial gain in power with the increase of sample size.
Journal ArticleDOI

Adaptive design methods in clinical trials – a review

TL;DR: Several commonly considered adaptive designs in clinical trials are reviewed and some examples concerning the development of Velcade intended for multiple myeloma and non-Hodgkin's lymphoma are given.
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Adaptive Group Sequential Designs for Clinical Trials: Combining the Advantages of Adaptive and of Classical Group Sequential Approaches

TL;DR: A general method is presented integrating the concept of adaptive interim analyses into classical group sequential testing to allow the researcher to represent every group sequential plan as an adaptive trial design and to make design changes during the course of the trial after every interim analysis.
References
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Journal ArticleDOI

Sample size increase during a survival trial when interim results are promising

TL;DR: In this paper, the authors extend Mehta and Pocock (2011) to provide a way in doing sample size increase in survival trials by dividing the sample space by observed test statistic at interim into three zones: un...
Posted Content

Analysis of "Learn-As-You-Go" (LAGO) Studies

TL;DR: In this paper, the authors developed methods for estimating the intervention effects in a learn-as-you-go (LAGO) adaptive studies, where the intervention is a complex package consisting of multiple components, and is adapted in stages during the study based on past outcome data.
Journal ArticleDOI

A Two-Stage Adaptive Design in Phase 2 Clinical Trials for Acute Treatment of Migraine

TL;DR: An adaptive two-stage dose-finding design is introduced that combines traditional phase 2a and 2b to serve the dual purpose of proof of concept and dose finding through the use of an unblinded interim analysis that provides an opportunity for adaptation.

Optimal Design and Adaptive Design in Stereology

Wei Zhang
TL;DR: This dissertation focuses on studies that examine the number of neurons in a brain region of interest using stereological techniques in order to compare subjects in different diagnostic groups, e.