Heitjan D F, Moskowitz A J, Whang W
Division of Biostatistics, International Center for Health Outcomes and Innovation Research, Columbia University, New York, New York, USA.
Med Decis Making. 1999 Jan-Mar;19(1):9-15. doi: 10.1177/0272989X9901900102.
The defining feature of a confidence interval is that it has a fixed minimum probability of covering the true value of the parameter being estimated, whatever the value of the parameter. The authors demonstrate by simulation that some recently proposed methods for interval estimation of the incremental cost-effectiveness ratio (ICER) either do not satisfy this definition or have other problems that limit their usefulness in applications. The problems are most prominent when the ICER is large and the true effectiveness difference is small relative to its standard error. A modification of the percentile bootstrap confidence interval that involves a reordering of the sample space provides a partial solution of the problem.
置信区间的定义特征是，无论参数的值如何，它都有一个固定的最小概率覆盖被估计参数的真实值。作者通过模拟证明，一些最近提出的增量成本效益比（ICER）区间估计方法要么不满足这个定义，要么存在其他问题，限制了它们在实际应用中的效用。当ICER很大且真实效果差异相对于其标准误差较小时，这些问题最为突出。对百分位数自助置信区间进行修改，涉及对样本空间重新排序，可部分解决该问题。
