Deployment experiences and motor vehicle crashes among U.S. service members.

BACKGROUND: Motor vehicle crashes (MVCs) continue to account for a third of service member fatalities each year. Sociodemographic factors associated with MVCs among service members have been evaluated, but whether deployment-specific experiences during the recent operations are associated with a higher risk of MVCs is unclear.

PURPOSE: Evaluate if military members with specific deployment experiences are at an increased risk of MVCs, while taking into account several potential confounders.

METHODS: Millennium Cohort Study participants who enrolled during 2001-2006 and were on active-duty service were evaluated. The Military Health System Data Repository (MDR) was used to investigate MVC-related injuries occurring 6 months postdeployment in relation to service-related factors, while adjusting for demographic, behavioral, and mental and physical health factors. Analysis conducted in 2012 used Cox proportional hazards modeling.

RESULTS: There were 13,620 deployed personnel included in this study. After adjusting for covariates, deployers with combat experiences (hazard ratio [HR]=1.86, 95% CI=1.33, 2.62) and those with more than one deployment (two deployments, HR=1.93, 95% CI=1.32, 2.83; three or more deployments, HR=2.83, 95% CI=1.71, 4.67) had an increased risk for an MVC within 6 months postdeployment. Enlisted rank and non-Hispanic black race/ethnicity were also associated with increased risk for MVCs.

CONCLUSION: Experiencing combat during deployment and multiple deployments are both strong predictors for MVCs within 6 months of returning home among U.S. military members. These data provide critical information for targeting prevention strategies to decrease MVCs among personnel postdeployment.