2007 National Roadside Survey of Alcohol and Drug Use by Drivers

2007 National Roadside Survey of Alcohol and Drug Use by Drivers: Drug ResultsTable 110. Nighttime Drug Prevalence by Time of Day (Oral Fluid and/or Blood)Time of DayN(Unweighted)% Drug Positive(Weighted)Daytime NA NANighttime 5,910 16.3%When we examined drug prevalence by time of day (Table 111), we found that late-night(Sessions 3 and 5) drivers were significantly more likely to be drug positive (19.1% and 18.3%respectively) than Friday and Saturday earlier in the night (Sessions 2 and 4) drivers (15.4% and15.2% respectively) (p < .01).Table 111. Drug Prevalence by Session (Oral Fluid and/or Blood)SessionN(Unweighted)% Drug Positive(Weighted)2: Friday, 10:00 p.m. – Midnight 1,618 15.4%3: Friday, 1:00 a.m. – 3:00 a.m. 1,313 19.1%4: Saturday, 10:00 p.m. – Midnight 1,695 15.2%5: Saturday, 1:00 a.m. – 3:00 a.m. 1,284 18.3%Overall 5,910 16.3%Comparison of drug prevalence by region (Table 112) showed that the Northeast region had thegreatest percentage of drug-positive findings, at 18.3 percent. However, this difference was notstatistically significant. Thus, no clear pattern by region emerged.Table 112. Drug Prevalence by Region (Oral Fluid and/or Blood)RegionN(Unweighted)% Drug Positive(Weighted)Midwest 1,708 16.9%Northeast 1,119 18.3%South 1,566 16.3%West 1,517 15.0%Overall 5,910 16.3%Examining drug prevalence by gender (Table 113) revealed that male drivers were significantlymore likely to be drug-positive than female drivers (18.0% male vs. 13.8% female) (p < .01).90