Conference Program Home
  My Program

All Times EDT

Abstract Details

Activity Number: 555 - Novel Methods in Estimation Enhancement
Type: Contributed
Date/Time: Thursday, August 11, 2022 : 10:30 AM to 12:20 PM
Sponsor: Biopharmaceutical Section
Abstract #323476
Title: Validity of Tests for Time-to-Event Endpoints in Studies with Minimization
Author(s): Victoria P Johnson* and Michael Gekhtman and Olga Kuznetsova
Companies: GSK and University of Notre Dame and Merck
Keywords: valid inference; minimization; log-rank test; covariate-adaptive randomization; survival analysis
Abstract:

The theory on valid inference about the treatment effect with time-to-event endpoints and covariate-adaptive randomization has been lacking until very recently. If the model is misspecified in trials with stratified randomization, the widely applied robust score test [Lin and Wei (1989); https://doi.org/10.1080/01621459.1989.10478874] was shown to be conservative by the groundbreaking work of Ye and Shao (2020; https://doi.org/10.1111/rssb.12392). This result, however, was not established for minimization other than via simulations. Interestingly, model misspecification caused by the omission of some factors from the analysis model is more common in trials when minimization is warranted. This talk will present recent work by Johnson, Gekhtman and Kuznetsova (draft manuscript, 2022) which extends the theory developed by Ye and Shao (2020) to show that both the log-rank and the robust score tests are conservative under minimization if the model is misspecified.

These results warrant the regulators' consideration to relax the requirements for re-randomization tests in addition to the score and log-rank tests. This talk will raise awareness about these developments.


Authors who are presenting talks have a * after their name.

Back to the full JSM 2022 program