Mental health and turnover following an initial term of military service.

Objective: This study compared the rates of mental disorders between Marines who re-enlisted and Marines who separated after 1 term, distinguishing between Marines who were and were not recommended for re-enlistment.

Methods: Participants included 28,693 male Marines enlisting for 4-year terms between 2002 and 2003, including 9,338 who re-enlisted after 1 term, 18,177 who voluntarily separated after 1 term, and 1,184 who were not recommended for re-enlistment and separated after 1 term.

Results: Analysis revealed disproportionately high rates of mental disorders among Marines not recommended for re-enlistment (Odds Ratio = 8.5, 95% Confidence Interval 7.5-9.8) compared with Marines who re-enlisted. Mental disorder prevalence was also elevated among service members who voluntarily separated after 1 term (Odds Ratio = 1.2, 95% Confidence Interval 1.1-1.3). Several specific categories of disorders, including personality disorders, substance use disorders, and post-traumatic stress disorder, predicted re-enlistment status.

Conclusions: These results suggest that mental disorders influence personnel retention in diverse ways, including heightened turnover, which could have a substantial impact on military manpower costs.