|
Activity Number:
|
418
|
|
Type:
|
Contributed
|
|
Date/Time:
|
Wednesday, August 1, 2007 : 10:30 AM to 12:20 PM
|
|
Sponsor:
|
Biopharmaceutical Section
|
| Abstract - #308581 |
|
Title:
|
A Supremum Log-Rank Test for Adaptive Two-Stage Treatment Strategies and Corresponding Sample Size Formula
|
|
Author(s):
|
Wentao Feng*+ and Abdus S. Wahed+
|
|
Companies:
|
University of Pittsburgh and University of Pittsburgh
|
|
Address:
|
3754 Allendale Circle, Pittsburgh, PA, 15204, , , ,
|
|
Keywords:
|
Adaptive treatment strategies ; Counting process ; Proportional hazards ; Sample size formula ; Supremum log rank statistics ; Survival Function
|
|
Abstract:
|
In two-stage adaptive treatment strategies, patients receive one of the induction treatments, followed by a maintenance therapy given that the patient responded to the induction therapy. To test the difference in the effect of different induction and maintenance treatment combinations, a modified supremum weighted log-rank test is proposed. The test is applied to the data from a two-stage randomized trial for illustration and compared with standard weighted log rank test. A sample size formula is proposed based on the limiting distribution of the supremum weighted log-rank statistic. Monte Carlo simulation studies show that the proposed test provides sample sizes which are close to that obtained by standard weighted log-rank test under proportional hazard alternative. The test is more powerful than standard weighted log-rank test under non-proportional hazard alternatives.
|