Reducing Alcohol-Impaired Driving: Maintaining Current Minimum Legal Drinking Age (MLDA) Laws
MLDA laws specify an age below which the purchase or public consumption of alcoholic beverages is illegal. In the United States, the age in all states is currently 21 years.
Summary of Task Force Recommendations and Findings
The Community Preventive Services Task Force recommends maintaining current minimum legal drinking age laws based on strong evidence of their effectiveness in reducing alcohol-related crashes and associated injuries among 18- to 20-year-old drivers.
Results from the Systematic Review
Thirty-three studies qualified for the systematic review.
- Most of the studies assessed the effects of changes in the MLDA from ages 18 to 21 or vice versa.
- Effects of raising the MLDA: crash-related outcomes decreased by median of 16% (14 studies; 1 study evaluating fatal crashes among 16-17 year olds was not included in the summary effect measures)
- Effects of lowering the MLDA: crash-related outcomes increased by median of 10% (9 studies)
- Estimated effect of raising the MLDA by 3 years (from 18 to 21) from regression-based studies: crash-related outcomes decreased by a median of 12% (9 studies)
- Effects were stable over follow-up times ranging from 7 to 108 months.
These results are based on a systematic review of all available studies led by scientists from CDC’s Division of Unintentional Injury Prevention with input from a team of specialists in systematic review methods and experts in research, practice and policy related to reducing alcohol-impaired driving.
- Analytic Framework – see Figure 1 on page 67 [PDF - 2.29 MB]
- Evidence Gaps
- Summary Evidence Tables* [PDF - 102 kB]
- Included Studies
- Search Strategy
Shults RA, Elder RW, Sleet DA, et al. Reviews of evidence regarding interventions to reduce alcohol-impaired driving. [PDF - 67 kB] Am J Prev Med 2001;21(4S):66–88.
Task Force on Community Preventive Services. Recommendations to reduce injuries to motor vehicle occupants: increasing child safety seat use, increasing safety belt use, and reducing alcohol-impaired driving. [PDF - 2.30 MB] Am J Prev Med 2001;21(4S):16–22.
Task Force on Community Preventive Services. Motor-vehicle occupant injury: strategies for increasing use of child safety seats, increasing use of safety belts, and reducing alcohol-impaired driving. MMWR Recommendations and Reports 2001;50(RR07):1-13.
Task Force on Community Preventive Services. Motor vehicle occupant injury. [PDF - 355 kB] In : Zaza S, Briss PA, Harris KW, eds. The Guide to Community Preventive Services: What Works to Promote Health? Atlanta (GA): Oxford University Press;2005:329-84.
Read other Community Guide publications about Motor Vehicle-Related Injury Prevention in our library.
*PDF includes all of the information available and will not be updated.
The findings and conclusions on this page are those of the Community Preventive Services Task Force and do not necessarily represent those of CDC. Task Force evidence-based recommendations are not mandates for compliance or spending. Instead, they provide information and options for decision makers and stakeholders to consider when determining which programs, services, and policies best meet the needs, preferences, available resources, and constraints of their constituents.
The content of publications of the Guide to Community Preventive Services is in the public domain. Citation as to source, however, is appreciated. Sample citation:
Guide to Community Preventive Services. Reducing alcohol-impaired driving: maintaining current minimum legal drinking age laws. www.thecommunityguide.org/mvoi/AID/mlda-laws.html. Last updated: MM/DD/YYYY.
Review completed: August 2000
- Page last reviewed: September 24, 2013
- Page last updated: September 24, 2013
- Content source: The Guide to Community Preventive Services