Alternative variance and efficiency calculations for the case-cohort design
病例队列设计的替代方差与效率计算
We define a bootstrap sampling plan for the case-cohort design and present bootstrap variance estimates and confidence intervals for the log relative hazard. The coverages of these confidence intervals are found to be near nominal levels in simulations. A simple null variance calculation, based on a superpopulation model, is shown to provide good estimates of the power and efficiency of the case-cohort design.