Measuring Soldier Performance During the Patrol-Exertion Multitask: Preliminary Validation of a Postconcussive Functional Return-to-Duty Metric

To assess the discriminant validity of the Patrol-Exertion Multitask (PEMT), a novel, multidomain, functional return-to-duty clinical assessment for active duty military personnel. Measurement development study. Nonclinical indoor testing facility. Participants (N=84) were healthy control (HC) service members (SMs; n=51) and military personnel (n=33) with persistent postconcussive symptoms receiving rehabilitation (mild traumatic brain injury [mTBI]). Not applicable. Known-groups discriminant validity was evaluated by comparing performance on the PEMT in 2 groups of active duty SMs: HCs and personnel with mTBI residual symptoms. Participant PEMT performance was based on responses in 4 subtasks during a 12-minute patrolling scenario: (1) accuracy in identifying virtual improvised explosive device (IED) markers and responses to scenario-derived questions from a computer-simulated foot patrol; (2) auditory reaction time responses; (3) rating of perceived exertion during stepping; and (4) self-reported visual clarity (ie, gaze stability) during vertical head-in-space translation while stepping. Significant between-group differences for the PEMT were observed in 2 of 4 performance domains. Postpatrol IED identification task/question responses (P=.179) and rating of perceived exertion (P=.133) did not discriminate between groups. Participant self-report of visual clarity during stepping revealed significant (P