title: Likelihood-based inferences about the mean area under a longitudinal curve in the presence of observations subject to limits of detection.
abstract: Comparison of groups in longitudinal studies is often conducted using the area under the outcome versus time curve. However, outcomes may be subject to censoring due to a limit of detection and specific methods that take informative missingness into account need to be applied. In this article, we present a unified model-based method that accounts for both the within-subject variability in the estimation of the area under the curve as well as the missingness mechanism in the event of censoring. Simulation results demonstrate that our proposed method has a significant advantage over traditionally implemented methods with regards to its inferential properties. A working example from an AIDS study is presented to demonstrate the applicability of our approach.
authors.affiliation: Department of Biostatistics, Vanderbilt University School of Medicine, Nashville, TN, USA.
authors.forename: Rameela
authors.initials: R
authors.lastname: Chandrasekhar
authors.affiliation: Department of Biostatistics, University at Buffalo, Buffalo, NY, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of Biostatistics, University at Buffalo, Buffalo, NY, USA.
authors.forename: Alan D
authors.initials: AD
authors.lastname: Hutson
authors.affiliation: Department of Biostatistics, University at Buffalo, Buffalo, NY, USA.
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Wilding
mesh_terms: D019540:Area Under Curve; D015982:Bias; D003627:Data Interpretation, Statistical; D004311:Double-Blind Method; D015658:HIV Infections / Q000188:drug therapy; D017320:HIV Protease Inhibitors / Q000627:therapeutic use; D006801:Humans; D016013:Likelihood Functions; D057230:Limit of Detection; D008137:Longitudinal Studies; D015233:Models, Statistical; D016032:Randomized Controlled Trials as Topic / Q000379:methods; D016896:Treatment Outcome; D019562:Viral Load / Q000187:drug effects
chemical_list: D017320:HIV Protease Inhibitors