Deployment Related Mild Traumatic Brain Injury (mTBI)

The study will provide evidence on the long term outcomes of mTBI in service members
returning from Afghanistan and Iraq. In addition, the study will provide evidence on mTBI
incidence, and symptom patterns. Self-reported assessments at baseline and follow-ups will be
combined with data on health care utilization and military job performance. The work,
symptoms, and family interaction outcomes of returning soldiers screening positive for mTBI,
combined mTBI and PTSD, and soldier controls will be compared at 3 months, 6 months, and at
one year. The assessments over time will permit descriptions of symptom changes for these
populations. It is likely the study will find similar findings to those of previous civilian
studies - that concussive symptoms often resolve within months of injury. However, some
soldier subsets may have chronic problems. Determining the incidence and outcomes of
individuals with mTBI will assist medical providers in determining the types of follow-ups
needed by returning service members and suggest the development of additional treatment
interventions. These results may also inform treatment of civilian populations with mTBI.

The three primary hypotheses are:

1. Concussive symptoms at the time of return from serving in Afghanistan and Iraq and
symptoms persisting 3 months, 6 months, and 12 months after return will be associated
with extent of exposure to combat, injury mechanism, associated injuries (co-occuring
injuries), PTSD and other psychiatric co-morbidities, and number of deployment-related
mTBIs.

2. Returning troops reporting concussive symptoms at the time of return from deployment
will have more work related problems at each follow-up (including lower rates of return
to duty, return to work, and poor quality of work).

3. The mTBI screening tool will be sensitive and specific to mTBI when compared to the
criterion measure, which is a structured interview conducted by clinicians blinded to
the screening results.