Results of the 2007 National Roadside Survey of Alcohol and Drug Use by Drivers

Results are presented from the 2007 National Roadside Survey (NRS) of Alcohol and Drug Use by Drivers, a nationally-representative sample of drivers in the United States. Data were collected at 300 sites in the contiguous US. The objective of the NRS was to: (1) determine the incidence of drivers at various Blood Alcohol Content (BAC) levels (and compare with three previous surveys); and (2) for the first time, estimate the incidence of drug use (over-the-counter, prescription, illegal) among drivers. Data were collected primarily on weekend nights; one daytime collection period (Friday) was included. Results showed that the proportion of weekend nighttime drivers with a BAC ≥ .08 g/dL declined over the years since 1973 (first roadside survey) from 7.5% (1973) to 2.2% (2007). Based on oral fluid analysis, more nighttime drivers (14.4%) were drug-positive than were daytime drivers (11.0%). Oral fluid analysis also indicated that 5.8% of daytime drivers and 10.5% of nighttime drivers tested positive for illegal drugs, while 4.8% of daytime drivers and 3.0% of nighttime drivers tested positive for medications. In reviewing these results, readers are cautioned that drug presence does not necessarily imply impairment. For many drug types, drug presence can be detected long after any impairment that might affect driving has passed. The full significance of these findings for highway safety will not be clear until additional research is completed.