Abstract
Two parametric tests are proposed for designing randomized two-arm phase III survival trials under the Weibull model. The properties of the two parametric tests are compared with the nonparametric log-rank test through simulation studies. Power and sample size formulas of the two parametric tests are derived. The sensitivity of sample size under misspecification of the Weibull shape parameter is also investigated. The study can be designed by planning the study duration and handling nonuniform entry and loss to follow-up under theWeibull model using either the proposed parametric tests or the well-known nonparametric log-rank test.
| Original language | English |
|---|---|
| Pages (from-to) | 16-28 |
| Number of pages | 13 |
| Journal | Journal of Biopharmaceutical Statistics |
| Volume | 25 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 2 2015 |
Bibliographical note
Funding Information:The work was supported in part by National Cancer Institute (NCI) support grant CA21765 and the American Lebanese Syrian Associated Charities (ALSAC).
Publisher Copyright:
© 2015, Taylor and Francis Inc. All rights reserved.
Keywords
- Log-rank test
- Proportional hazards model
- Randomized clinical trial
- Sample size
- Time-to-event
- Weibull distribution
ASJC Scopus subject areas
- Statistics and Probability
- Pharmacology
- Pharmacology (medical)