The stability of engagement over comprehensive neuropsychological assessment in student athletes diagnosed with sports related concussion.

We documented effort stability during neuropsychological (NP) testing examining failure rates on three Performance Validity Tests (PVTs). 65 student athletes, ages 8-21, were evaluated in an outpatient practice, following sports-related concussion over three sessions within 18 months of injury (mean=6 months). 7.7% of student athletes failed PVTs at all three test sessions, 7.7% failed PVTs at two test sessions, and 12.3% failed PVTs at one session; 28% of this sample was sub-optimally engaged for at least one test session, producing invalid neuropsychological data at the time of testing and 72% produced valid neuropsychological data across the comprehensive evaluation.