P.Mean: Cytel software has developed a Poisson model for predicting accrual (created 2008-07-09).
I attended a web seminar by Jeff Palmer, Cytel Corporation, about Bayesian methods in adaptive clinical trials. It was a very good seminar, and I should try to summarize some of the major points sometime. One of the figures, though, caught my attention. It showed a projection of future accrual based on a Poisson distribution.
This is similar to our work, though we use an exponential waiting time distribution to model the waiting time between successive patients. A later slide discussed how to predict the number of events in a survival analysis model based on a prediction for patients that are in the study who have not yet experienced an event and a prediction on patients who have not yet entered into the trial.
As I mentioned in an earlier weblog entry, there is a publication in Statistics in Medicine that uses a Poisson model for accrual.
As an odd coincidence, Amazon sent me an email encouraging me to buy a new book on adaptive clinical trials. This book mentions ExPDesign studio, which has its own website. I do not have the book or the software, so I cannot make any comments other than it looks interesting.
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