title: Bayesian Model Assessment in Joint Modeling of Longitudinal and Survival Data with Applications to Cancer Clinical Trials.
abstract: Joint models for longitudinal and survival data are routinely used in clinical trials or other studies to assess a treatment effect while accounting for longitudinal measures such as patient-reported outcomes (PROs). In the Bayesian framework, the deviance information criterion (DIC) and the logarithm of the pseudo marginal likelihood (LPML) are two well-known Bayesian criteria for comparing joint models. However, these criteria do not provide separate assessments of each component of the joint model. In this paper, we develop a novel decomposition of DIC and LPML to assess the fit of the longitudinal and survival components of the joint model, separately. Based on this decomposition, we then propose new Bayesian model assessment criteria, namely, ΔDIC and ΔLPML, to determine the importance and contribution of the longitudinal (survival) data to the model fit of the survival (longitudinal) data. Moreover, we develop an efficient Monte Carlo method for computing the Conditional Predictive Ordinate (CPO) statistics in the joint modeling setting. A simulation study is conducted to examine the empirical performance of the proposed criteria and the proposed methodology is further applied to a case study in mesothelioma.
authors.affiliation: Gilead Sciences, Inc., 333 Lakeside Drive, Foster City, CA 94404, U.S.A.
authors.forename: Danjie
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Department of Statistics, University of Connecticut, 215 Glenbrook Road, U-4120, Storrs, CT 06269, U.S.A.
authors.forename: Ming-Hui
authors.initials: MH
authors.lastname: Chen
authors.affiliation: Department of Biostatistics, University of North Carolina, McGavran Greenberg Hall, CB#7420, Chapel Hill, NC 27599, U.S.A.
authors.forename: Joseph G
authors.initials: JG
authors.lastname: Ibrahim
authors.affiliation: Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN 46285, U.S.A.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Boye
authors.affiliation: Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN 46285, U.S.A.
authors.forename: Wei
authors.initials: W
authors.lastname: Shen
keywords: CPO; DIC; LPML; Monte Carlo method; Patient-reported outcome (PRO)