Weighted Approach for Estimating Effects in Principal Strata With Missing Data for a Categorical Post-Baseline Variable in Randomized Controlled Trials
Weighted Approach for Estimating Effects in Principal Strata With Missing Data for a Categorical Post-Baseline Variable in Randomized Controlled Trials
复制标题
随机对照试验中分类基线后变量缺失数据的主层效应估计的加权方法
DOI：
10.1080/19466315.2021.2009020
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发表时间：
2021
影响因子：
1.8
通讯作者：
Lu Tian
中科院分区：
文献类型：
--
作者：
S. Kong;D. Heinzmann;S. Lauer;Lu Tian
本研究的动机是在一项随机对照试验中研究抗药物抗体（ADA）的形成及其对生物治疗长期获益的潜在影响，在该试验中，不仅在对照组中未观察到ADA状态，而且在实验治疗组的一部分患者中也未观察到ADA状态。最近的文献考虑了主要的地层估计策略，以评估由互流状态定义的患者组的治疗效果，即由仅在一只臂中观察到的随机化后变量定义的组，并且可能与结果相关。然而，即使对于实验组中不可忽略的数量的患者，状态信息也可能缺失。针对这种情况，提出了一种新的加权主层方法，即加权归算回归（WRI）：基于基线协变量和其他纵向信息，对缺少互流事件状态的患者数据进行重新加权。为不同类型的结果提供了WRI方法的理论依据，并对允许对治疗效果得出因果结论的假设进行了具体说明和调查。模拟表明，WRI方法产生了有效的推理，并且对某些违反假设的情况具有鲁棒性。该方法在ADA作为并发事件的临床研究中表现良好。
Abstract This research was motivated by studying anti-drug antibody (ADA) formation and its potential impact on long-term benefit of a biologic treatment in a randomized controlled trial, in which ADA status was not only unobserved in the control arm but also in a subset of patients from the experimental treatment arm. Recent literature considers the principal stratum estimand strategy to estimate treatment effect in groups of patients defined by an intercurrent status, that is, in groups defined by a post-randomization variable only observed in one arm and potentially associated with the outcome. However, status information might be missing even for a nonnegligible number of patients in the experimental arm. For this setting, a novel weighted principal stratum approach, namely weighted imputation regression (WRI), is presented: Data from patients with missing intercurrent event status were re-weighted based on baseline covariates and additional longitudinal information. A theoretical justification of the WRI method is provided for different types of outcomes, and assumptions allowing for causal conclusions on treatment effect are specified and investigated. Simulations demonstrated that the WRI method yielded valid inference and was robust against certain violations of assumptions. The method was shown to perform well in a clinical study with ADA status as an intercurrent event.
(2)基于身体部位特征点和形状信息的模型步态认证研究
DOI：
--
发表时间：
2015
期刊：
影响因子：
--
作者：
井元大輔;黒沢健至;土屋兼一;黒木健郎;秋葉教充;角田英俊
通讯作者：
角田英俊