Comment on “Analysis of Longitudinal Trials With Protocol Deviations: A Framework for Relevant, Accessible Assumptions, and Inference via Multiple Imputation,” by Carpenter, Roger, and Kenward
نویسندگان
چکیده
Carpenter et al. (2013) propose a multiple imputation (MI) approach for analyzing data from clinical trials with protocol deviations. Sensitivity analysis to departures from missing at random (MAR) is widely acknowledged as important, but is poorly handled in practice, so we welcome their detailed proposals. However, here we highlight two problems with their method: an implicit assumption of noninformative deviation, and failure of the Rubin’s Rule (RR) variance estimator.
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عنوان ژورنال:
دوره 24 شماره
صفحات -
تاریخ انتشار 2014