Program Profile: Community-Level Intervention on Alcohol-Related Motor Vehicle Crashes (Calif.)

This program was designed to reduce excessive drinking among adolescents and young adults ages 12-25 through community-wide enforcement operations and awareness campaigns. The program is rated Promising. There was a statistically significant reduction in alcohol-related motor vehicle crashes among 15- to 30-year-old drivers in treatment group cities, compared with control group cities.

A Promising rating implies that implementing the program may result in the intended outcome(s).

This program's rating is based on evidence that includes either 1) one study conducted in multiple sites; or 2) two or three studies, each conducted at a different site. Learn about how we make the multisite determination.

Program Goals/Target Population

The Community-Level Intervention on Alcohol-Related Motor Vehicle Crashes was created under a partnership between California’s Department of Alcohol and Drug Programs and a grant from the Substance Abuse and Mental Health Services Administration. The overall goal was to develop a systematic approach to alcohol use prevention that would expedite the adoption of evidence-based strategies. The grant focused on reducing excessive drinking among adolescents and young adults ages 12 to 25, with priority given to the type of drinking that presents the greatest risk to the community, such as binge drinking (i.e., five or more drinks in a row for men and four or more drinks in a row for women; HHS 2019).

Program Components

The program uses alcohol enforcement operations conducted by local law enforcement agencies. These enforcement operations include sobriety checkpoints and saturation patrols to reduce drunk driving, and undercover operations in bars or other licensed on-premises establishments to reduce alcohol service to intoxicated patrons.

Visibility activities consist of publicizing local enforcement operations through different media channels (e.g., radio, social media, mobile signs, marquees at high schools), periodic bar visits by local enforcement officers, and letters to owners or managers of licensed on-premises establishments. In most of the cities that implemented the intervention, a community-based organization was also involved in publicizing law enforcement operations in collaboration with local law enforcement agencies. Law enforcement agencies and community-based organizations were expected to implement at least two high-visibility law enforcement operations per quarter.

Study

Saltz and colleagues (2021) conducted a randomized matched-case trial assessing the effects of California’s community-level alcohol prevention interventions on reducing alcohol-related motor vehicle crashes among drivers ages 15−30. All medium-sized cities (50,000−450,000 population) were assessed for inclusion in the study; there were 138 medium-sized cities identified from the 2000 census. The study authors then created a subset of 50 cities through a process of random selection, which was modified to avoid selecting two neighboring cities. Cities were matched via cluster analysis using a combination of demographic characteristics (e.g., population size, ethnic composition), based on 2011 census data, and the prevalence of alcohol-related problems (high consumption, alcohol-related crashes, underage drinking).

A total of 24 California cities were matched into pairs before randomly assigning 12 cities each to the treatment group and control group. Treatment group cities received high visibility, driving under the influence (DUI) enforcement operations (e.g., sobriety checkpoints and saturation patrols to provide visible enforcement of drink driving laws, public awareness media such as posters and mobile signs), from April 2013 to March 2016. The control group cities did not receive any high-visibility DUI enforcement operations during the same period. There were no statistically significant differences in demographic characteristics between the treatment group cities and the control group cities. The treatment group’s average city population size was 104,512, and 26.9 percent of the population identified as an ethnic minority. The control group’s average city population size was 101,751, and 27.8 percent of the population identified as an ethnic minority. Drivers ages 15−30 were involved in 57.6 percent of all motor vehicle crashes and 44.0 percent of single-vehicle nighttime crashes in treatment group cities during the study period, compared with 61.3 percent and 46.9 percent, respectively, in control group cities.

The outcome of interest was a monthly percentage of all motor vehicle crashes that were single-vehicle, alcohol-related nighttime crashes for drivers ages 15−30. Multilevel analyses were conducted to examine treatment effects on alcohol-related crashes among drivers. Data from the California Statewide Integrated Traffic Records System was used to create a monthly measure of alcohol-related motor vehicle crashes for each city from January 2010 through April 2016. The study authors computed the percentage of all motor vehicle crashes that were single-vehicle, alcohol-related nighttime crashes for drivers ages 15−30 (and for all drivers). A continuous time variable representing 76 months was created for the analyses, and the analyses used a random effects model. Robust standard errors were used to account for the non-normal distribution of dependent variables. The study authors also conducted subgroup analyses on treatment dosage.

Saltz and associates (2021) conducted a cost–benefit ratio for California’s community-level alcohol prevention interventions on reducing alcohol-related motor vehicle crashes. Each of the 12 treatment communities was provided with funding of $95,000 per year over the 3-year treatment period, of which the total was approximately $3,420,000. Estimates of the cost of an alcohol-involved crash (including fatal, injury, and property damage-only crashes) came to a total of $296,127. Therefore, a reduction of 310 crashes translates to a savings of $91 million, which means that the cost–benefit ratio is approximately 27:1 or $27 saved for every $1 spent.

The State of California budgeted approximately $95,000 per year for each community site, which was typically allocated to county health departments or to local agencies.

A key to implementation of the grant was the use of two logic models specifying the components to be used at all of the community sites. The logic models (the first for reducing underage alcohol consumption and the second for reducing alcohol-impaired driving aimed at young adults) identified key objectives based on research literature. The key objectives were to 1) enhance enforcement of drinking and driving laws; 2) improve retail serving practices; 3) reduce social availability, especially to minors; and 4) reduce retail availability to minors.

The communities were asked to implement at least two operations per quarter with accompanying visibility. In most cities, law enforcement agencies carried out the operations component, whereas a local prevention agency took responsibility for obtaining the visibility component. Law enforcement operations were conducted as random roadside DUI checkpoints. The visibility component included public service announcements on the radio, announcements at high school sporting events, and portable marquees on trailers to warn of local DUI enforcement.

Subgroup Analysis

Saltz and colleagues (2021) conducted a subgroup analysis on the moderating effects of California’s community-level alcohol prevention interventions on reducing alcohol-related motor vehicle crashes among drivers ages 15-30. The study authors found that a greater effect was seen in cities with a lower dosage (i.e., no more than two high-visibility DUI operations per quarter) for drivers ages 15–30, compared with cities that implemented more than two high-visibility DUI operations. This difference was statistically significant.

These sources were used in the development of the program profile:

These sources were used in the development of the program profile:

HHS (U.S. Department of Health and Human Services), Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration. 2019. “Key Substance Use and Mental Health Indicators in the United States: Results from the 2018 National Survey on Drug Use and Health.” (HHS Publication No. PEP19-5068, NSDUH Series H-54). Rockville, Md.: HHS, Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration.