Background: Motor vehicle crashes are the leading cause of death in the United States among persons aged 5-34 years. Seat belts have been shown to be the most effective method for reducing injuries among adults in the event of a crash.
Methods: CDC used 2009 data from the National Electronic Injury Surveillance System--All Injury Program (NEISS-AIP) to provide U.S. estimates of the number and rate of nonfatal, motor vehicle--occupant injuries treated in emergency departments among adults aged ≥18 years. In addition, CDC used 2008 data from the Behavioral Risk Factor Surveillance System (BRFSS) to estimate the prevalence of self-reported seat belt use among adults in the United States. Seat belt use was examined further by type of state seat belt enforcement law.
Results: In 2009 in the United States, an estimated 2.3 million adult motor vehicle--occupants had nonfatal injuries treated in emergency departments. The nonfatal, motor vehicle--occupant injury rate declined 15.6% from 1,193.8 per 100,000 population in 2001 to 1,007.5 per 100,000 population in 2009. In 2008, self-reported seat belt use was higher in states with primary enforcement laws (88.2%), compared with states with secondary enforcement laws (79.2%). If the secondary law states had achieved 88.2% seat belt use in 2008, an additional 7.3 million adults would have been belted. From 2002 to 2008, self-reported seat belt use increased overall from 80.5% to 85.0%.
Conclusions: Nonfatal, motor vehicle--occupant injuries treated in emergency departments have declined in recent years but still affect a substantial proportion of the adult U.S. population each year. Self-reported belt use increased from 2002 to 2008, and was higher in states with primary enforcement laws compared with states with secondary enforcement laws.
Implications for public health practice: Seat belt use is a proven method to reduce motor vehicle--occupant injuries, and the results of this analysis demonstrate that states with primary enforcement laws have higher prevalence of self-reported seat belt use. To help reduce the number of motor vehicle--occupant injuries, 19 states without primary enforcement laws should consider enacting them.