Balancing events, not patients, maximizes power of the logrank test: and other insights on unequal randomization in survival trials

Autor:	Yung, Godwin, Rufibach, Kaspar, Wolbers, Marcel, Lin, Ray, Liu, Yi
Rok vydání:	2024
Předmět:	Statistics - Methodology Statistics - Applications
Druh dokumentu:	Working Paper
Popis:	We revisit the question of what randomization ratio (RR) maximizes power of the logrank test in event-driven survival trials under proportional hazards (PH). By comparing three approximations of the logrank test (Schoenfeld, Freedman, Rubinstein) to empirical simulations, we find that the RR that maximizes power is the RR that balances number of events across treatment arms at the end of the trial. This contradicts the common misconception implied by Schoenfeld's approximation that 1:1 randomization maximizes power. Besides power, we consider other factors that might influence the choice of RR (accrual, trial duration, sample size, etc.). We perform simulations to better understand how unequal randomization might impact these factors in practice. Altogether, we derive 6 insights to guide statisticians in the design of survival trials considering unequal randomization. Comment: 17 pages, 3 figures, 2 tables
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2407.03420 Zobrazit plný text záznamu View this record from Arxiv