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Activity Number:
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239
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Type:
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Contributed
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Date/Time:
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Tuesday, August 5, 2008 : 8:30 AM to 10:20 AM
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Sponsor:
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Biometrics Section
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| Abstract - #301298 |
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Title:
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Estimating Cumulative Treatment Effects in the Presence of Nonproportional Hazards and Dependent Censoring
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Author(s):
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Guanghui Wei*+ and Douglas E. Schaubel
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Companies:
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The University of Michigan and The University of Michigan
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Address:
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Department of Biostatistics, U of Michigan, Ann Arbor, MI, 48109,
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Keywords:
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Dependent censoring ; IPCW ; IPTW ; Nonparametric estimtor ; Survival analysis ; Time-dependent effect
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Abstract:
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In medical studies featuring survival time data, non-proportional hazards and dependent censoring are very common issues when estimating the treatment effect. We propose a measure for estimating the cumulative treatment effect in the presence of non-proportional hazards. The proposed estimator is computed by first using inverse probability of treatment weighting (IPTW) to balance the treatment-specific covariate distributions. At the next stage, Inverse probability of censoring weighting (IPCW) is applied to handle the dependent censoring due to known prognostic factors. Asymptotic properties of the proposed estimator are derived, and the finite-sample properties are assessed in simulation studies. The proposed method is applied to organ failure data.
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