title: Analysis of longitudinal censored semicontinuous data with application to the study of executive dysfunction: The Towers Task.
abstract: Executive dysfunction is a deficiency in skills of planning and problem solving that characterizes many neuropsychiatric disorders. The Towers Task is a commonly used measure of planning and problem solving for assessing executive function. Towers Task data are usually zero-inflated and right-censored, and ignoring these features can result in biased inference for the disease characterization of executive dysfunction. In this manuscript, a mixed-effects model for longitudinal censored semicontinuous data is developed for analyzing longitudinal Towers Task data from the PREDICT-HD study. The model is contrasted with current practice, and implications for general use are discussed.
authors.affiliation: 1 Department of Biostatistics, University of Iowa, Iowa City, USA.
authors.forename: Spencer
authors.initials: S
authors.lastname: Lourens
authors.affiliation: 2 Department of Biostatistics, Indiana University Fairbanks School of Public Health and School of Medicine, Indianapolis, USA.|3 Department of Mathematics, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: 4 Departments of Psychiatry and Biostatistics, University of Iowa, Iowa City, USA.
authors.forename: Jeffrey D
authors.initials: JD
authors.lastname: Long
authors.affiliation: 5 Departments of Psychiatry, Neurology and Psychology, Carver College of Medicine, University of Iowa, Iowa City, USA.
authors.forename: Jane S
authors.initials: JS
authors.lastname: Paulsen
mesh_terms: D000328:Adult; D056808:Biostatistics / Q000379:methods; D003198:Computer Simulation; D003627:Data Interpretation, Statistical; D018450:Disease Progression; D056344:Executive Function; D005260:Female; D006801:Humans; D006816:Huntington Disease / Q000523:psychology; D016013:Likelihood Functions; D008137:Longitudinal Studies; D008297:Male; D015233:Models, Statistical; D017711:Nonlinear Dynamics; D011340:Problem Solving; D013647:Task Performance and Analysis
keywords: Cognitive neuroscience; Huntington disease; Towers Task; censored data; mixed-effect model; semicontinuous data