Department of Statistics, Yunnan University, Kunming 650091, PR China.
Stat Methods Med Res. 2011 Jun;20(3):233-59. doi: 10.1177/0962280209358135. Epub 2010 Feb 24.
Bilateral dichotomous data are very common in modern medical comparative studies (e.g. comparison of two treatments in ophthalmologic, orthopaedic and otolaryngologic studies) in which information involving paired organs (e.g. eyes, ears and hips) is available from each subject. In this article, we study various confidence interval estimators for proportion difference based on Wald-type statistics, Fieller theorem, likelihood ratio statistic, score statistics and bootstrap resampling method under the dependence or/and independence models for bilateral binary data. Performance is evaluated with respect to the coverage probability and expected width via simulation studies. Our empirical results show that (1) ignoring the dependence feature of bilateral data could lead to severely incorrect coverage probabilities; and (2) Wald-type, score-type and bootstrap confidence intervals based on the dependence model perform satisfactorily for small to large sample sizes in the sense that their empirical coverage probabilities are close to the pre-specified nominal confidence level and are hence recommended. A real data from an otolaryngologic study is used to illustrate the proposed methods.
双边二分数据在现代医学比较研究中非常常见（例如眼科、骨科和耳鼻喉科研究中比较两种治疗方法），其中每个受试者的配对器官（例如眼睛、耳朵和臀部）都有相关信息。在本文中，我们研究了双边二项数据的依赖或/和独立模型下基于 Wald 型统计量、Fieller 定理、似然比统计量、得分统计量和自举重抽样方法的比例差异的各种置信区间估计。通过模拟研究，根据覆盖概率和期望宽度评估性能。我们的实证结果表明：（1）忽略双边数据的相关性特征可能会导致严重不正确的覆盖概率；（2）基于依赖模型的 Wald 型、得分型和自举置信区间在小到大样本量的情况下表现良好，因为它们的经验覆盖概率接近预设的名义置信水平，因此建议使用。来自耳鼻喉科研究的真实数据用于说明所提出的方法。
