In this article, sample size calculations are developed for use when the main interest is in the differences between the cure rates of two groups. Following the work of Ewell and Ibrahim, the asymptotic distribution of the weighted log-rank test is derived under the local alternative. The optimal log-rank test under the proportional distributions alternative is discussed, and sample size formulas for the optimal and standard log-rank tests are derived. Simulation results show that the proposed formulas provide adequate sample size estimation for trial designs and that the optimal log-rank test is more efficient than the standard log-rank test, particularly when both cure rates and percentages of censoring are small.
|Number of pages||11|
|Journal||Journal of Biopharmaceutical Statistics|
|State||Published - Jan 2 2017|
Bibliographical noteFunding Information:
This work was supported in part by the National Cancer Institute support grant CA21765 and ALSAC.
© 2017 Taylor & Francis.
- Clinical trial
- cure model
- log-rank test
- optimal test
- sample size
ASJC Scopus subject areas
- Statistics and Probability
- Pharmacology (medical)