Dong Ting, Tang Liansheng Larry, Rosenberger William F
George Mason University, Fairfax, USA.
J R Stat Soc Ser C Appl Stat. 2014 Apr;63(3):499-514. doi: 10.1111/rssc.12043.
A subjective sampling ratio between the case and the control groups is not always an efficient choice to maximize the power or to minimize the total required sample size in comparative diagnostic trials.We derive explicit expressions for an optimal sampling ratio based on a common variance structure shared by several existing summary statistics of the receiver operating characteristic curve. We propose a two-stage procedure to estimate adaptively the optimal ratio without pilot data. We investigate the properties of the proposed method through theoretical proofs, extensive simulation studies and a real example in cancer diagnostic studies.
在比较诊断试验中,病例组与对照组之间采用主观抽样比例并非总是最大化检验效能或最小化所需总样本量的有效选择。我们基于接收器操作特征曲线的几个现有汇总统计量共有的方差结构,推导出最优抽样比例的显式表达式。我们提出一种两阶段程序,无需预试验数据即可自适应估计最优比例。我们通过理论证明、广泛的模拟研究以及癌症诊断研究中的一个实际例子,研究了所提方法的性质。