Abstract
In clinical trials, continuous monitoring is required when a large but nonsignificant test statistic is observed at an interim analysis. We consider a power family of continuous stopping boundaries that are optimal in the sense that they minimize the average stopping time for the given overall Type I error rate and power. The problem is formulated as a constrained optimization problem and is solved numerically using the differential evolution algorithm. The main results are the ready-to-use approximately optimal continuous stopping boundaries for a wide range of values of power and the most commonly used overall levels of significance.
ACKNOWLEDGMENTS
This research is supported by a Davis Fellowship, awarded by the College of Business Administration, Rider University. I thank Dr. Benjamin H. Eichhom for helpful discussions.
Notes
Recommended by Nitis Mukhopadhyay