A successful high-visibility enforcement intervention targeting underage drinking drivers

AIMS

To measure the effectiveness of a high-visibility enforcement campaign to reduce rates of underage drinking and driving.

DESIGN

Mixed-model analysis compares rates of drinking and driving (1) between the baseline and intervention period and (2) between the baseline and follow-up period. The impact of the intervention was evaluated using roadside surveys and web surveys.

SETTING

Two college-town communities in the mid-Atlantic region of the United States.

PARTICIPANTS

Study participants consisted of 6825 drivers stopped, interviewed and breathalyzed on weekend nights. Web survey data were collected from 2061 students from large state universities in each community.

INTERVENTION

Increased high-visibility enforcement of drinking and driving laws, featuring the use of passive alcohol sensors by police, along with a coordinated publicity campaign.

MEASURES

Roadside surveys measured breath alcohol concentrations (BrAC) of drivers. The web surveys measured self-reported drinking.

FINDINGS

Mixed-model analysis revealed a statistically significant reduction in drivers with BrACs ≥ 0.08 g/dl during the intervention and follow-up periods, F(2, 5744)  = 6.5, P < 0.01. The web-survey revealed that students under age 21 also reported significantly less driving after drinking during the intervention and follow-up periods, F(2, 1767)  = 4.6, P < 0.01.

CONCLUSIONS

A high-visibility enforcement campaign targeting underage drinking and driving appeared to reduce both underage driving after drinking among US college students as well as drunk driving (breath alcohol concentration ≥ 0.08 g/dl) at any age..

International trends in alcohol and drug use among vehicle drivers

Trends in the use of alcohol and drugs among motor vehicle drivers in Australia, Brazil, Norway, Spain, and the United States have been reviewed. Laws, regulations, enforcement, and studies on alcohol and drugs in biological samples from motor vehicle drivers in general road traffic and fatal road traffic crashes (RTCs) are discussed. Roadside surveys showed a reduction of drunk driving over time in the studied countries; however, the pattern varied within and between different countries. The reduction of alcohol use may be related to changes in road traffic laws, public information campaigns, and enforcement, including implementation of random breath testing or sobriety checkpoints. For non-alcohol drugs, the trend in general road traffic is an increase in use. However, drugs were not included in older studies; it is therefore impossible to assess the trends over longer time periods. Data from the studied countries, except Brazil, have shown a significant decrease in fatal RTCs per 100,000 inhabitants over the last decades; from 18.6 to 4.9 in Australia, 14.5 to 2.9 in Norway, 11.1 to 3.6 in Spain, and 19.3 to 10.3 in the United States. The number of alcohol-related fatal RTCs also decreased during the same time period. The proportion of fatal RTCs related to non-alcohol drugs increased, particularly for cannabis and stimulants. A general challenge when comparing alcohol and drug findings in biological samples from several countries is connected to differences in study design, particularly the time period for performing roadside surveys, biological matrix types, drugs included in the analytical program, and the cutoff limits used for evaluation of results. For RTC fatalities, the cases included are based on the police requests for legal autopsy or drug testing, which may introduce a significant selection bias. General comparisons between high-income countries and low- and middle-income countries as well as a discussion of possible future trends are included.

Drinking and driving in the United States: comparing results from the 2007 and 1996 National Roadside Surveys

OBJECTIVES

The objectives of this study were to (a) use data from the 2007 National Roadside Survey (NRS) to determine the characteristics of weekend nighttime drivers with positive blood alcohol concentrations (BACs) on U.S. roads in 2007; (b) determine the relationship of the driving environment and trip characteristics associated with drinking drivers; and (c) compare the findings for the 2007 NRS with those for the 1996 NRS.

METHODS

Like the 1996 NRS, the 2007 NRS used a stratified random national roadside survey sample of the contiguous 48 states and collected nighttime data on Fridays and Saturdays between 10 p.m. and 3 a.m. Officers directed 8384 drivers into off-road parking areas where our research team asked them to participate in the survey.

RESULTS

Of those approached, 7159 (85.4%) provided a breath test. Results revealed that 12 percent of the nighttime drivers had positive BACs, and of those, 2 percent were higher than the 0.08 BAC illegal limit in the United States. Since the 1996 NRS, we found significant reductions in the percentage of BAC-positive drivers across different demographic groups. Age was among the most significant factors associated with a weekend driver having a positive BAC. The probability that a driver would be drinking peaked in the 21- to 25-year-old age group. Male drivers were more likely than female drivers to be drinking, and Asian and Hispanic drivers were less likely than white drivers to be drinking. Drinking drivers were more likely to be driving short distances (5 or fewer miles) late at night (between 1 and 3 a.m.) and to be coming from a bar or restaurant. Finally, 26 percent of the drivers who reported that they would drive less than 5 miles on the night of the survey had positive BACs, compared to only 16 percent who indicated that they would drive between 6 and 20 miles and 10 percent who planned to drive more than 20 miles.

CONCLUSIONS

The 2007 NRS provides another benchmark in the 4-decade record of drinking drivers on American roads and provides a basis for measuring progress in combating driving under the influence during the coming decade.

Toward national estimates of alcohol use disorders among drivers: results from the National Roadside Survey Pilot Program

OBJECTIVE

To determine whether drivers contacted at the roadside can be screened for alcohol use disorders (AUDs). Secondarily, to produce preliminary estimates of AUDs among drivers and estimate the relationship between AUD status and BAC measured at the roadside.

METHODS

A two-phase survey program was undertaken. In phase 1, 206 motorists were interviewed at the roadside using a 15-item AUD Survey derived from a condensed version of the AUDADIS and the AUDIT-C. One hundred sixty-seven of these motorists were invited, for a $25 incentive, to call the research team within 48 h of the roadside assessment to repeat the questionnaire and complete a more detailed AUD assessment. Phase 2 involved a 6-state pilot test of the AUD Survey as an add-on to the 2005 National Roadside Survey Pilot Program. The setting for both phases of the survey program was US roadways on weekends between 10 p.m. and 3 a.m.

RESULTS

Ninety-seven percent of all eligible drivers completed the AUD questionnaire. The correlation between roadside and telephone interview results was 0.3 for alcohol abuse, 0.6 for alcohol dependence and heavy drinking, and 0.7 for binge drinking. Alcohol abuse and dependence diagnoses had 0.6 and 0.7 correlations with diagnoses derived from the full AUDADIS and the AUDIT-C had a 0.8 correlation with the full AUDIT. There was also a statistically significant and positive relationship between having a positive BAC at the roadside and meeting criteria for heavy drinking.

CONCLUSIONS

AUD status can be effectively measured at the roadside. The poor reliability for alcohol abuse is related to underreporting of drinking and driving during roadside assessments, compared to telephone follow-up. Other measures of hazardous alcohol use should be used in the roadside context to measure alcohol abuse.