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CDC COMMUNITY GUIDE: Reducing Alcohol-Impaired Driving: Ignition Interlocks

CDC

An Evidence-Based Practice

Description

An ignition interlock is a device that can be installed in a motor vehicle to prevent a driver who has a blood alcohol concentration (BAC) above a specified level (usually 0.02% to 0.04%) from driving the vehicle. Interlocks are most often installed in vehicles of people who have been convicted of alcohol-impaired driving to give them an opportunity to drive legally.

Impact

The Community Preventive Services Task Force (CPSTF) recommends the use of ignition interlocks for people convicted of alcohol-impaired driving based on evidence that they reduce re-arrest rates while the interlocks are installed.

Public health benefits of ignition interlock interventions are currently limited by the small proportion of offenders who install interlocks in their vehicles. More widespread and sustained use of interlocks among this population could have a greater impact on alcohol-related crashes.

Results / Accomplishments

The CPSTF recommendation was based on results from two systematic reviews that considered a total of 15 studies.

While interlocks were installed, re-arrest rates decreased by a median of 67% relative to comparison groups (13 studies). This estimate is based on all of the available studies that reported separate results for re-arrests during the interlock installation period.
When interlocks were removed, re-arrest rates reverted to rates similar to those of persons convicted of alcohol-impaired driving who had not used interlocks (11 studies).
Drivers with interlocks installed had fewer alcohol-related crashes than those who had licenses suspended for an alcohol-impaired driving conviction (1 study).
Overall, drivers with ignition interlocks had crash rates similar to those of the general driving population. Drivers with interlocks, however, had a substantially greater number of crashes overall than did drivers with suspended licenses. This is likely because those with ignition interlocks drove more than those with suspended licenses (2 studies).

About this Promising Practice

Primary Contact
The Community Guide
1600 Clifton Rd, NE
MS E69
Atlanta, GA 30329
(404) 498-1827
communityguide@cdc.gov
https://www.thecommunityguide.org/
Topics
Health / Prevention & Safety
Health / Alcohol & Drug Use
Community / Public Safety
Source
Community Guide Branch Epidemiology and Analysis Program Office, Centers for Disease Control and Prevention
Location
USA
For more details
Target Audience
Adults
Coastal Georgia Indicators Coalition