Analysis of Subgroup Effects in Randomized Tri- als When Subgroup Membership is Informatively Missing: Application to the MADIT II Study
نویسندگان
چکیده
In this paper, we develop and implement a methodology for drawing inference about subgroup effects in a two-arm randomized trial when subgroup status is only known for a non-random sample in each of the trial arms. The methodology is developed in the context of the MADIT II study, a randomized trial designed to evaluate the effectiveness of implantable defibrillators on survival.
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