Sample-size formula for clustered survival data using weighted log-rank statistics
基于加权对数秩统计量的聚类生存数据样本量公式
We present a simple sample‐size formula for weighted log‐rank statistics applied to clustered survival data with variable cluster sizes and arbitrary treatment assignments within clusters. This formula is based on the asymptotic normality of weighted log‐rank statistics under certain local alternatives in the clustered data context. We also provide consistent variance estimators. The derived sample‐size formula reduces to Schoenfeld's (1983) formula for cases of no…