The 2007 National Roadside Survey (NRS) is a national field survey of alcohol- and drug-involved driving conducted primarily among nighttime weekend drivers, but also daytime Friday drivers. The survey involved randomly selecting drivers at 300 locations across the continental United States; sites were selected through a stratified random sampling procedure. This included data that collected during a two-hour Friday daytime session at 60 locations and during four 2-hour nighttime periods (10 p.m.-midnight and 1-3 a.m. on both Friday and Saturday) at 240 locations. Participation was voluntary and anonymous.

This study estimated drug prevalence. 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 cannot be used to draw conclusions about drug-impaired driving.

There are 3 reports in this series. Volume 1 describes the methodology, Volume 2 presents the alcohol results, and Volume 3 presents the drug results.

• Volume I: Methodology
• Volume II: Alcohol Results
• Volume III: Drug Results
• Research Note