Bayesian Joint Modeling of Zero-Inflated Panel Count and Severity Outcomes

• Activity Number: 409
• Type: Topic Contributed
• Date/Time: Tuesday, August 6, 2013 : 2:00 PM to 3:50 PM
• Sponsor: International Indian Statistical Association
• Author(s): Elizabeth Juarez-Colunga*+ and Giovani Silva and Charmaine Dean
• Companies: University of Colorado Denver and Technical University of Lisbon and University of Western Ontario
• Keywords: counting process ; marks ; life-history data ; longitudinal data ; poisson regression

Abstract

Panel counts are often encountered in clinical studies where individuals are followed over time and the number of events occurring in time intervals, or panels, are recorded. This talk discusses methods for situations where, in addition to the counts of events, we also record a mark, denoting a measure of prognostic factors or severity of the events. In many situations there is an association between the recurring processes and their marks. This occurs in the motivating example for this work, a study of the effects of two hormone therapy treatments in reducing vasomotor symptoms in healthy menstruating women prior to hysterectomy/ovariectomy for benign disease. We model the event counts and their severities jointly through the use of shared or linking random effects. We also compare this approach to the common practice of analyzing a composite measure built as the number of events multiplied by their severity.