title: Longitudinal Studies With Outcome-Dependent Follow-up: Models and Bayesian Regression.
abstract: We propose Bayesian parametric and semiparametric partially linear regression methods to analyze the outcome-dependent follow-up data when the random time of a follow-up measurement of an individual depends on the history of both observed longitudinal outcomes and previous measurement times. We begin with the investigation of the simplifying assumptions of Lipsitz, Fitzmaurice, Ibrahim, Gelber, and Lipshultz, and present a new model for analyzing such data by allowing subject-specific correlations for the longitudinal response and by introducing a subject-specific latent variable to accommodate the association between the longitudinal measurements and the follow-up times. An extensive simulation study shows that our Bayesian partially linear regression method facilitates accurate estimation of the true regression line and the regression parameters. We illustrate our new methodology using data from a longitudinal observational study.
authors.affiliation: Duchman Ryu is  . Debajyoti Sihna is Professor, Department of Biostatistics, Bioinformatics, and EPI, Medical University of South Carolina, Charleston, SC 29425 (E-mail:  sinhad@musc.edu ). Bani Mallick is Professor, Department of Statistics, Texas A&M University, College Station, TX 77843 (E-mail:  bmallick@stat.tamu.edu ). S. L. Lipsitz is  . S. Lipshultz is.
authors.forename: Duchwan
authors.initials: D
authors.lastname: Ryu
authors.forename: Debajyoti
authors.initials: D
authors.lastname: Sinha
authors.forename: Bani
authors.initials: B
authors.lastname: Mallick
authors.forename: S L
authors.initials: SL
authors.lastname: Lipsitz
authors.forename: S
authors.initials: S
authors.lastname: Lipshultz