Objective: Examine differences in the results of neuropsychological assessment as a function of time since injury following pediatric concussion.
Participants and Methods: 121 youth seen in a specialty concussion clinic (55% female, mean age=13.71) were administered the WISC-V or WAIS-IV working memory (WMI) and processing speed (PSI) indices. A separate group of 307 participants (41% female, mean age= 14.81) were administered the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). Individuals were split into two groups based on the number of days since injury (1-10 days and 11-20 days). Parents completed the Post Concussion Symptom Inventory (PCSI) and scores were adjusted for retrospective pre-injury ratings.
Results: Overall, youth seen within 3 weeks of injury demonstrated average cognitive performance (although some individuals fell 1.5 SDs or more below the mean; 7% WMI, 10% PSI, 17% ImPACT verbal memory, 19% ImPACT visual memory, 15% ImPACT processing speed, 26% ImPACT reaction time). No group level differences in test performance were found as a function of time since injury. Moreover, time since injury was not associated with most performance-based measures of cognitive functioning after controlling for GPA, age, gender, and symptom burden. Greater deficits in ImPACT processing speed and reaction time was associated with longer time since injury, although time since injury predicted only two percent of the total variance. In contrast, symptom burden was associated with worse performance in processing speed (WISC-V/WAIS-IV and ImPACT), reaction time (ImPACT), and verbal memory (ImPACT).
Conclusions: Cognitive test performance following pediatric concussion was age appropriate for most and time since injury was not a robust predictor of performance. However, up to 26% did perform poorly on testing. Cognitive performance was associated with parent-reported symptom burden. Impairment on cognitive testing may indicate the need for close clinician monitoring and greater supports within the academic setting.