Williamson John M, Crawford Sara B, Lin Hung-Mo
Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA.
J Biopharm Stat. 2007;17(4):685-96. doi: 10.1080/10543400701329471.
The concordance correlation coefficient (CCC) is a popular index for measuring the reproducibility of continuous variables. We examine two resampling approaches, permutation testing and the bootstrap, for conducting hypothesis tests on dependent CCCs obtained from the same sample. Resampling methods are flexible, require minimal marginal and joint distributional assumptions, and do not rely on large sample theory. However, the permutation test requires a restrictive assumption (exchangeability) which limits its applicability in this situation. Simulation results indicate that inference based on the bootstrap is valid, although type-I error rates are inflated for small sample sizes ( approximately 30). For illustration we analyze data from a carotid stenosis screening study.
一致性相关系数(CCC)是衡量连续变量可重复性的常用指标。我们研究了两种重抽样方法,即置换检验和自助法,用于对从同一样本中获得的相关CCC进行假设检验。重抽样方法灵活,所需的边际和联合分布假设最少,且不依赖大样本理论。然而,置换检验需要一个严格的假设(可交换性),这限制了它在这种情况下的适用性。模拟结果表明,基于自助法的推断是有效的,尽管对于小样本量(约30),I型错误率会膨胀。为了说明,我们分析了一项颈动脉狭窄筛查研究的数据。