Modeling Bicyclist Injury Severity: A Focus on the Impact of Alcohol and Drug Use

This study examined the impact of alcohol and drug use on bicyclist injuries caused by bicycle-motor vehicle crashes. The authors used six-year data from the city of Jacksonville, Florida. Descriptive statistics results showed that with data involving alcohol/drugs there was 22.12% incapacitating injury outcomes and 16.81% fatal outcomes while with the data not involving alcohol/drugs there was 11.11% incapacitating injury outcomes and only 1.25% fatal outcomes. Due to this discrepancy, crashes involving alcohol and/or drug use and those not involving alcohol and/or drug use were analyzed separately to identify whether there exist specific factors explaining the discrepancy in injury severity among the two groups. In addition to estimating separate multinomial logit (MNL) models for each data set, a model was estimated using combined data. Both MNL models estimated with separate data indicated that the following factors which were identified as significant with combined data were not significant: night time, fault motor vehicle turning right and fault motor vehicle changing lanes. However, whether the crash occurred at the intersection and whether the roadway surface was dry were significant variables in the models estimated with separate sub-data but not in the combined-data analysis. To compare the effect of the variables on injury severity for crashes involving alcohol/drugs and those not involving alcohol/drugs, the authors computed elasticities. The results indicated that variables that are significantly affecting the injury outcome when considering crashes involving alcohol and/or drug use are not necessarily significant when considering crashes not involving alcohol and/or drug use. Even when a variable was found to be influential on both data sets, there was a difference in what bicyclist injury severity is impacted. The only factors found to have effect on severity for both sub-data sets (although inconsistent on the direction of the effect on some injury levels) were bicyclist age and whether or not the crash occurred on dry surface.

• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Kwigizile, Valerian
  • Sando, Thobias
  • Chimba, Deo
• Conference:
  • Transportation Research Board 91st Annual Meeting
  • Location: Washington DC, United States
  • Date: 2012-1-22 to 2012-1-26
• Date: 2012

Language

• English

Media Info

• Media Type: Digital/other
• Features: References; Tables;
• Pagination: 19p
• Monograph Title: TRB 91st Annual Meeting Compendium of Papers DVD

Subject/Index Terms

• TRT Terms: Alcohol use; Bicycle crashes; Crash injuries; Cyclists; Drug use; Injury severity; Multinomial logits
• Geographic Terms: Jacksonville (Florida)
• Subject Areas: Highways; Pedestrians and Bicyclists; Safety and Human Factors; I83: Accidents and the Human Factor; I84: Personal Injuries;

Filing Info

• Accession Number: 01365432
• Record Type: Publication
• Report/Paper Numbers: 12-0057
• Files: TRIS, TRB
• Created Date: Mar 20 2012 12:16PM