To investigate cognitive function and other risk factors for mild traumatic brain injury in young men.
Nationwide prospective cohort study.
Sweden.
305?885 men conscripted for military service from 1989 to 1994.
mild traumatic brain injuries in relation to cognitive function and other potential risk factors assessed at conscription and follow-up.
Men with one mild traumatic brain injury within two years before (n=1988) or after cognitive testing (n=2214) had about 5.5% lower overall cognitive function scores than did men with no mild traumatic brain injury during follow up (P