Driving, Drinking, and Drug Use
- Overview & Basic Data
- Estimates of Impairment & Risk
- Estimated DUID Prevalence
- Roadside Drug Testing Devices
- Other Specific Research Findings on Marijuana and Driving
- Laws & Policies
Page last updated June 10, 2020 by Doug McVay, Editor/Senior Policy Analyst.
16. Prevalence of Drug Use by Drivers in the US
"Based on the oral fluid results, more nighttime drivers (14.4%) were drug-positive then were daytime drivers (11.0%). Based on the blood test results which were administered only at nighttime, 13.8% of the drivers were drug-positive. Using the combined results of either or both oral fluid and blood tests, 16.3% of the nighttime drivers were drug-positive.
Compton, Richard and Berning, Amy, "Results of the 2007 National Roadside Survey of Alcohol and Drug Use by Drivers" (Washington, DC: Dept. of Transportation, National Highway Traffic Safety Administration, July 2009), DOT HS 811 175, p. 3.
17. Prevalence of Drug Use by Drivers in the US
"The recently published 2007 National Roadside Survey of Alcohol and Drug Use by Drivers: Drug Results reported the drug prevalence (detected by oral fluid and blood samples) in 7,719 weekend drivers who served as participants in the survey (Lacey et al., 2009). The prevalence of drugs in drivers tested during the daytime was 11%.1 Specifically, 5.8% tested positive for the category of illegal drugs, 4.8% for the medication category (i.e., prescription [Rx] and over-the-counter [OTC] medications), and 0.5% for the combined illegal and medication category. The nighttime survey results showed a prevalence of 14.4% for positive drug results. In this sample, 10.5% were positive for illegal drugs, 3% positive for the medication category, and 0.9% positive for the combined illegal and medication category. In addition, for those individuals who tested positive for illegal drugs (9.8%) the rate of those who also tested positive for alcohol was 28%. One of the major conclusions and recommendations of this study is that “further research is needed to determine the effect of drug prevalence on crash risk” (p.8)."
Kay, G. G., & Logan, B. K., (2011). Drugged Driving Expert Panel report: A consensus protocol for assessing the potential of drugs to impair driving. (DOT HS 811 438). Washington, DC: National Highway Traffic Safety Administration, p. 1.
18. Prevalence of Drugged Driving Estimated by NSDUH
"In 2011, 9.4 million persons or 3.7 percent of the population aged 12 or older reported driving under the influence of illicit drugs during the past year. This was a decrease from the rate in 2010 (4.2 percent) and the rate in 2002 (4.7 percent). Across age groups, the rate of driving under the influence of illicit drugs in 2011 was highest among young adults aged 18 to 25 (11.6 percent); this rate for young adults in 2011 was lower than the rate in 2010 (12.7 percent). Additionally, the rate of driving under the influence of illicit drugs during the past year decreased among adults aged 26 or older (from 2.9 percent in 2010 to 2.4 percent in 2011)."
Substance Abuse and Mental Health Services Administration, "Results from the 2011 National Survey on Drug Use and Health: Summary of National Findings," NSDUH Series H-44, HHS Publication No. (SMA) 12-4713. Rockville, MD: Substance Abuse and Mental Health Services Administration, 2012, p. 27
19. Prevalence Trends Of Substances Detected Among Drivers In Fatal Auto Accidents, 1999-2010
"When time trends of nonalcohol drugs were examined by drug class, the prevalence of narcotics tripled during the study period, increasing from 1.8% in 1999 (95% CI: 1.3, 2.6) to 5.4% (95% CI: 4.4, 6.8) in 2010 (Z = ?7.07, P < 0.0001, Figure 2), and the increase occurred in both sexes (Table 1). The prevalence of depressants (excluding alcohol) and other drugs also increased significantly over the study period (Z = ?4.54, P < 0.0001, and Z = ?2.61, P = 0.01, respectively). There was not a monotonic trend in the prevalence of stimulants during the study period (Figure 2). Overall, the prevalence of cannabinol nearly tripled over the study period, increasing from 4.2% (95% CI: 3.3, 5.2) in 1999 to 12.2% (95% CI: 10.6, 14.1) in 2010 (Z = ?13.63, P < 0.0001, Figure 2), and the upward trends in the prevalence of cannabinol were similar for men and women (Table 1). By the end of the study period, cannabinol became the most prevalent nonalcohol drug detected in fatally injured drivers (Figure 2). The prevalence of cannabinol increased significantly across age groups (Figure 3). The increase in the prevalence of cannabinol was most pronounced among fatally injured drivers less than 25 years of age (Figure 3)."
Joanne E. Brady and Guohua Li. "Trends in Alcohol and Other Drugs Detected in Fatally Injured Drivers in the United States, 1999–2010." American Journal of Epidemiology. (2014) 179 (6): 692-699. doi: 10.1093/aje/kwt327.
20. Prevalence of Drug Use Among Drivers
"Analyses of the oral fluid samples obtained from daytime drivers indicated an overall drug use prevalence of 11 percent, and for nighttime drivers, 14.4 percent (Table 19). This includes illegal, prescription, and over-the-counter drugs combined. This overall difference between day and night is statistically significant (p < .01).
Lacey, John H.; Kelley-Baker, Tara; Furr-Holden, Debra; Voas, Robert B.; Romano, Eduardo; Ramirez, Anthony; Brainard, Katharine; Moore, Christine; Torres, Pedro; and Berning, Amy , "2007 National Roadside Survey of Alcohol and Drug Use by Drivers," Pacific Institute for Research and Evaluation (Calverton, MD: National Highway Traffic Safety Administration, December 2009), p. 111.