JSM 2012 Home

JSM 2012 Online Program

The views expressed here are those of the individual authors and not necessarily those of the JSM sponsors, their officers, or their staff.

Online Program Home

Abstract Details

Activity Number: 318
Type: Topic Contributed
Date/Time: Tuesday, July 31, 2012 : 10:30 AM to 12:20 PM
Sponsor: Biopharmaceutical Section
Abstract - #306240
Title: Forecasting Enrollment in Clinical Trials When Site-Level Accrual Rates Vary with Time
Author(s): Yannis Jemiai*+ and Nitin Patel and Suresh Ankolekar and Pralay Senchaudhuri
Companies: Cytel Inc. and Cytel Inc. and Maastricht School of Management and Cytel Inc.
Address: 675 Massachusetts Ave., Cambridge, MA, 02139, United States
Keywords: Enrollment ; Forecasting ; Recruiting ; Gamma-Poisson ; Time varying enrollment rates ; Bayesian model

We have studied the performance of the Gamma-Poisson model of Anisimov and Federov (Stat Med, 2007) in forecasting enrollment using historical data from several Phase 2 and Phase 3 trials. We have focused on its ability to improve forecasts of trial completion time as the trial progresses. We find that while it is often adequate, there are several instances when the assumption of a constant Poisson rate for each center leads to substantial errors. We extend the model to accommodate time varying rates using a state-space model proposed by Harvey and Fernandes (J Bus Econ Stat, 1989) and report results from using this model on the historical data. We also examine a simpler approach using tracking errors to trigger user intervention to improve the forecasts.

The address information is for the authors that have a + after their name.
Authors who are presenting talks have a * after their name.

Back to the full JSM 2012 program

2012 JSM Online Program Home

For information, contact jsm@amstat.org or phone (888) 231-3473.

If you have questions about the Continuing Education program, please contact the Education Department.