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.