通过权衡解决集群随机实验中的选择偏差
Georgia Papadogeorgou1, Bo Liu2, Fan Li3,4
1Department of Statistics, University of Florida, Gainesville, FL 32611, United States.
Biometrics
|March 7, 2025
概括
随机化后招募的集群随机化试验可能会导致选择偏差. 本研究定义了因果估计值,并使用反向概率权重来估计招募人群中的治疗效应,解决集群随机实验中的偏差.
科学领域:
- 生物统计学 生物统计学
- 临床试验 临床试验
- 流行病学 流行病学
背景情况:
- 集群随机实验通常在治疗分配后招募参与者,从而导致潜在的选择偏差.
- 数据的可用性通常仅限于招募的样本,从而在总体和招募人群之间产生差异.
- 随机化后的招募可以在招募样本中引发干预和控制臂之间的系统差异.
研究的目的:
- 在随机化后招募的集群随机化实验中,为整体和招募人群定义因果估计值.
- 开发方法来估计治疗效果,尽管潜在的选择偏差.
- 在总人口中确定可估计治疗效果的有意义的子群体.
主要方法:
- 定义整体和招募人群的因果估计.
- 证明对被招募人群的平均治疗效果的一致估计,使用无视招募的逆概率权重.
- 使用主要分层来确定治疗对特定亚群的影响.
- 开发一个估计策略和敏感性分析,以忽略招聘假设.
- 在CRTrecruit R包中的实施方法.
主要成果:
- 在不可忽视的招聘假设下,可以使用反向概率加权来一致估计被招募人群的平均治疗效应.
- 治疗对整体人口的平均效果通常是无法识别的.
- 治疗效应可以确定子群体:那些总是被招募的和那些只在治疗中被招募的.
- 对ARTEMIS试验的应用显示,在总是招募的人群中,P2Y$_{12}$抑制剂的持久性增加.
结论:
- 提供了方法来解决集群随机化实验中的选择偏差,随机化后招募.
- 该研究提供了一个框架,用于估计特定亚群体的治疗效应,当整体人口效应无法识别时.
- CRTrecruit R包和灵敏度分析有助于在现实研究中应用和验证这些方法.
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