用倾向分数分层和平衡权重解决实质性共变量失衡问题:联系和建议
Laine E Thomas1, Steven M Thomas2, Fan Li3
1Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, USA.
Epidemiologic methods
|November 28, 2023
概括
重叠加权 (OW) 优于调整具有显著共变异不平衡的观察性研究中的混. 修剪方法可以引入偏差,除非模型重新调整,否则所有方法都与OW类似.
科学领域:
- 流行病学 流行病学
- 生物统计学 生物统计学
背景情况:
- 倾向性得分 (PS) 权衡方法对于调整观察性研究中的混至关重要.
- 极端的PS值 (接近0或1) 可能会导致膨胀的方差和不可靠的治疗效果估计,这是由于实质性的共同变量失衡.
研究的目的:
- 为了比较重叠权重 (OW) 与倾向分数分层 (PSS) 和修剪方法的性能.
- 为在具有显著共变量失衡的观察性研究中选择和实施PS方法提供实际建议.
主要方法:
- 分析推导,以建立不同PS方法之间的联系.
- 模拟研究,以评估各种权重和分层技术的偏差和差异.
主要成果:
- 叠加权重 (OW) 显示出优异的性能,特别是随着共变异不平衡的增加.
- 使用Mantle-Haenszel权重 (PSS-MH) 的倾向分数分层显示了与OW相似的性能,是OW的粗版本.
- 修剪方法,没有重新装配PS模型,增加了偏差;然而,重新装配导致了类似于OW的结果.
结论:
- 一般来说,对实质性的共变异不平衡来说,OW是首选的方法.
- PSS-MH提供了一个可行的替代方案,其性能与OW相似.
- 仔细实施,包括在修剪后重新装配模型,对于PS方法的准确结果至关重要.
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