Assurance calculations for planning clinical trials with time-to-event outcomes
Article first published online: 16 JUL 2013
Copyright © 2013 John Wiley & Sons, Ltd.
Statistics in Medicine
Volume 33, Issue 1, pages 31–45, 15 January 2014
How to Cite
Ren, S. and Oakley, J. E. (2014), Assurance calculations for planning clinical trials with time-to-event outcomes. Statist. Med., 33: 31–45. doi: 10.1002/sim.5916
- Issue published online: 10 DEC 2013
- Article first published online: 16 JUL 2013
- Manuscript Accepted: 24 JUN 2013
- Manuscript Received: 1 NOV 2012
- prior distribution;
- sample size;
- survival analysis
We consider the use of the assurance method in clinical trial planning. In the assurance method, which is an alternative to a power calculation, we calculate the probability of a clinical trial resulting in a successful outcome, via eliciting a prior probability distribution about the relevant treatment effect. This is typically a hybrid Bayesian-frequentist procedure, in that it is usually assumed that the trial data will be analysed using a frequentist hypothesis test, so that the prior distribution is only used to calculate the probability of observing the desired outcome in the frequentist test. We argue that assessing the probability of a successful clinical trial is a useful part of the trial planning process. We develop assurance methods to accommodate survival outcome measures, assuming both parametric and nonparametric models. We also develop prior elicitation procedures for each survival model so that the assurance calculations can be performed more easily and reliably. We have made free software available for implementing our methods. Copyright © 2013 John Wiley & Sons, Ltd.