title: Traffic environment and demographic factors affecting impaired driving and crashes.
abstract: BACKGROUND
  Data availability has forced researchers to examine separately the role of alcohol among drivers who crashed and drivers who did not crash. Such a separation fails to account fully for the transition from impaired driving to an alcohol-related crash.
  
  
  METHODS
  In this study, we analyzed recent data to investigate how traffic-related environments, conditions, and drivers' demographics shape the likelihood of a driver being either involved in a crash (alcohol impaired or not) or not involved in a crash (alcohol impaired or not). Our data, from a recent case-control study, included a comprehensive sampling of the drivers in nonfatal crashes and a matched set of comparison drivers in two U.S. locations. Multinomial logistic regression was applied to investigate the likelihood that a driver would crash or would not crash, either with a blood alcohol concentration (BAC)=.00 or with a BAC≥.05.
  
  
  CONCLUSIONS
  To our knowledge, this study is the first to examine how different driver characteristics and environmental factors simultaneously contribute to alcohol use by crash-involved and non-crash-involved drivers. This effort calls attention to the need for research on the simultaneous roles played by all the factors that may contribute to motor vehicle crashes.
authors.affiliation: Impaired Driving Center, PIRE, Pacific Institute for Research and Evaluation, 11720 Beltsville Drive, Suite 900, Calverton, MD 20705–3111, USA. romano@pire.org
authors.forename: Eduardo O
authors.initials: EO
authors.lastname: Romano
authors.forename: Raymond C
authors.initials: RC
authors.lastname: Peck
authors.forename: Robert B
authors.initials: RB
authors.lastname: Voas
mesh_terms: D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D000428:Alcohol Drinking; D003710:Demography; D004777:Environment; D006801:Humans; D016013:Likelihood Functions; D016015:Logistic Models; D012307:Risk Factors; D014481:United States; D014887:Weather