Development and Initial Evaluation of a Dynamic Marksmanship Battery: Sensitivity to Vestibular Disturbances Relevant to Return-to-Duty

Abstract

Mild traumatic brain injuries (mTBI) have been diagnosed in 261,480 service-members in the past decade. This study aimed to evaluate the initial reliability and validity of a military-specific task battery to assess gross vestibular function and functional balance in service-members to aid in return-to-duty decision making. Four dynamic marksmanship tasks was developed to mimic the types of balance and movement challenges well-documented among patients with mTBI, including head turns (pivot and shoot task), picking up an object from the floor (pick-up and shoot task), rapidly walking a straight line (traverse beam and shoot task), and balancing with a reduced base of support (kneel and shoot task). Test-retest reliability, sensitivity to vestibular disturbance created by chair rotation (construct validity), and ability to distinguish soldiers with and without mTBI (known-groups validity) were evaluated. Results showed acceptable test-retest reliability for two of the four tasks and found the other two tasks to be sensitive to temporary vestibular insult in healthy controls. Additionally, the pick-up and shoot task distinguished mTBI soldiers with vestibular symptoms from a control group. The pick up and shoot task showed acceptable test-retest reliability and support for known-groups validity, thus likely the best task from the battery for future research.