Power and sample size calculation for paired recurrent events data based on robust nonparametric tests.
The purpose of this paper is to develop a formula for calculating the required sample size for paired recurrent events data. The developed formula is based on robust non-parametric tests for comparing the marginal mean function of events between paired samples. This calculation can accommodate the associations among a sequence of paired recurrent event times with a specification of correlated gamma frailty variables for a proportional intensity model. We evaluate the performance of the proposed method with comprehensive simulations including the impacts of paired correlations, homogeneous or nonhomogeneous processes, marginal hazard rates, censoring rate, accrual and follow-up times, as well as the sensitivity analysis for the assumption of the frailty distribution. The use of the formula is also demonstrated using a premature infant study from the neonatal intensive care unit of a tertiary center in southern Taiwan. Copyright © 2017 John Wiley & Sons, Ltd.
Department of Statistics, National Cheng Kung University, Tainan, 70101, Taiwan.
Pei-Fang
0000-0002-1149-8022
PF
Su
Department of Statistics, National Cheng Kung University, Tainan, 70101, Taiwan.
Chia-Hua
CH
Chung
Institute of Allied Health Science, National Cheng Kung University, Tainan, 70101, Taiwan.
Yu-Wen
YW
Wang
Department of Statistics, National Cheng Kung University, Tainan, 70101, Taiwan.
Yunchan
Y
Chi
Institute of Allied Health Science, National Cheng Kung University, Tainan, 70101, Taiwan.|Department of Nursing, National Cheng Kung University, Tainan, 70101, Taiwan.
Ying-Ju
YJ
Chang
D006801:Humans; D015233:Models, Statistical; D012008:Recurrence; D018401:Sample Size; D018709:Statistics, Nonparametric
correlated gamma frailty; cumulative mean function; mixed Poisson process; non-parametric test