Drug and Alcohol Crash Risk

While the extent of use of alcohol by drivers and the risks posed by alcohol use have been well known for many decades, relatively little has been known about the use of other drugs by drivers and the associated risks. However, drug-impaired driving has recently become an issue of increasing public and governmental concern in the United States and in many other countries. While it is readily apparent that driving-related skills can be impaired by a wide variety of illegal substances and medications, the nature and scope of the drug-impaired driving problem has been difficult to define. In the United States, recent State actions to legalize the use of marijuana for medical and recreational use have further exacerbated concern over potential risks of driving impaired by marijuana. This case-control crash risk study is the first large-scale study in the United States to include drugs other than alcohol. It was designed to estimate the risk associated with alcohol- and drug-positive driving. Virginia Beach, Virginia, was selected for this study because of the outstanding cooperation of the local agencies and because the geographic area is large enough to provide a sufficient number of crashes for meaningful analysis. Data was collected from more than 3,000 crash-involved drivers and 6,000 control drivers (not involved in crashes). Breath alcohol measurements were obtained from a total of 10,221 drivers, oral fluid samples from 9,285 drivers, and blood samples from 1,764 drivers.

  • Supplemental Notes:
    • See "Drug and Alcohol Crash Risk" (DOT HS 812 117, February 2015) and "Drug and Alcohol Crash Risk: A Case-Control Study" (DOT HS 812 355, December 2016).


  • English


  • Status: Completed
  • Contract Numbers:


  • Sponsor Organizations:

    National Highway Traffic Safety Administration

    1200 New Jersey Avenue, SE
    Washington, D.C.  United States  20590
  • Project Managers:

    Berning, Amy

  • Performing Organizations:

    Pacific Institute for Research and Evaluation

    11720 Beltsville Drive, Ste 900
    Calverton, MD  United States  20705-3111
  • Start Date: 20060930
  • Expected Completion Date: 0
  • Actual Completion Date: 20161200
  • USDOT Program: Behavioral Safety Research
  • Subprogram: Alcohol Impaired Driving
  • Subprogram: Drug Impaired Driving

Subject/Index Terms

Filing Info

  • Accession Number: 01640760
  • Record Type: Research project
  • Source Agency: National Highway Traffic Safety Administration
  • Contract Numbers: DTNH22-06-C-00040
  • Files: RiP, USDOT
  • Created Date: Jul 6 2017 5:46PM