NHTSA’s “Crash Risk” study is the first large-scale study in the United States to include drugs other than alcohol. The case-control study was designed to estimate the risk associated with alcohol- and drug-positive driving. Data was collected over 20 months from more than 3000 crash-involved drivers and 6000 control drivers who were not involved in crashes in Virginia Beach, VA. Research teams responded to crashes 24 hours a day, 7 days a week over a 20-month period, and efforts were made to match control drivers to each crash-involved driver to maximize comparability. Participation was voluntary and anonymous. Participating subjects were asked to provide a breath test, oral fluid, and blood samples to determine the presence of alcohol and other drugs.

This study estimated the odds of being involved in a crash if a driver was alcohol- and/or drug-positive. A positive result for a drug does not necessarily mean the driver was impaired at the time of testing, only that the drug was present in the body. Data from this study contributes to a better understanding of the nature and scope of the drugged driving issue.

Data from this study is available in four formats: SAS, SPSS, Stata, and Excel; the data dictionary is compatible for all four file formats.

• SAS database
• SPSS database
• Stata database
• Excel database
• Data dictionary

A weighting variable is provided for application. Its construction is described in the methodology report.