Work

Adaptive Trial Designs

Year: 2011

Type: review

Abstract: We review adaptive designs for clinical trials, giving special attention to the control of the Type I error in late-phase confirmatory trials, when the trial planner wishes to adjust the final sample size of the study in response to an unblinded analysis of interim estimates of treatment effects. We point out that there is considerable inefficiency in using the adaptive designs that employ conditional power calculations to reestimate the sample size and that maintain the Type I error by using certain weighted test statistics. Although these adaptive designs have little advantage over familiar group-sequential designs, our review also describes recent developments in adaptive designs that are both flexible and efficient. We also discuss the use of Bayesian designs, when the context of use demands control over operating characteristics (Type I and II errors) and correction of the bias of estimated treatment effects.

Source: The Annual Review of Pharmacology and Toxicology

DOI: 10.1146/annurev-pharmtox-010611-134504

Authors: Tze Leung Lai, Philip William Lavori, Mei-Chiung Shih

Institutions: Stanford University, United States Department of Veterans Affairs

Language: English

Topic: Statistical Methods in Clinical Trials

Subfield: Statistics and Probability

Field: Mathematics

Domain: Physical Sciences

Open Access status: green

Funders: National Institutes of Health, National Cancer Institute, National Center for Research Resources, National Center for Advancing Translational Sciences

Awards: Spectrum Stanford Center for clinical and Translational Research and Education, Stanford Center for Clinical and Translational Education and Research (SCCTER)UL1, Stanford Cancer Institute