Suicides, homicides, accidents, and undetermined deaths in the U.S. military: comparisons to the U.S. population and by military separation status.

Purpose: To compare rates of external causes of mortality among individuals who served in the military (before and after separation from the military) to the U.S. population. Methods: This retrospective cohort study examined all 3.9 million service members who served from 2002 to 2007. External cause mortality data from 2002 to 2009 were used to calculate standardized mortality ratios. Negative binomial regression compared differences in the mortality rates for pre- and post-separation. Results: Accident and suicide mortality rates were highest among cohort members under 30 years of age, and most of the accident and suicide rates for these younger individuals exceeded expectation given the U.S. population mortality rates. Military suicide rates began below the expected U.S. rate in 2002 but exceeded the U.S. rate by 2009. Accident, homicide, and undetermined mortality rates remained below the U.S. rates throughout the study period. Mortality rates for all external causes were significantly higher among separated individuals compared with those who did not separate. Mortality rates for individuals after separation from service decreased over time but remained higher than the rates for those who had not separated from service. Conclusions: Higher rates of death for all external causes of mortality after separation suggest prevention opportunities. Future research should examine how preseparation characteristics and experiences may predict postseparation adverse outcomes to inform transition programs. Published by Elsevier Inc.