Negative Binomials Regression Model in Analysis of Wait Time at Hospital Emergency Department

• Activity Number: 520
• Type: Contributed
• Date/Time: Wednesday, August 6, 2014 : 10:30 AM to 12:20 PM
• Sponsor: Survey Research Methods Section
• Author(s): Bill Cai*+
• Companies: NCHS/DHCS
• Keywords: ED ; NHAMCS ; Wait Time ; Poisson Regression ; Negative Binomial Regression ; GEE

Abstract

Wait time is the differences between the time a patient arrives in the emergency department (ED) and the time an ED provider examines that patient. This study focuses on the development of a negative binomial model to examine factors associated with ED wait time using the National Hospital Ambulatory Medical Care Survey (NHAMCS). Conducted by National Center for Health Statistics (NCHS), NHAMCS has been gathering, analyzing, and disseminating information annually about visits made for medical care to hospital outpatient department and EDs since 1992. To analyze ED wait times, a negative binomial model is fit to the ED visit data using publically released micro data from the 2009 NHAMCS. In this model, the wait time is the dependent variable while hospital, patient, and visit characteristics are the independent variables. Wait time is collapsed into discrete values representing 15 minutes intervals. The findings are presented.