Abstract
OBJECTIVE: We examined cognitive performance in children with complicated mild-severe traumatic brain injury (TBI) versus orthopedic injury (OI) using the National Institutes of Health Toolbox Cognitive Battery (NIH TB-CB). METHOD: We recruited children ages 3-18, hospitalized with complicated mild-severe TBI (n = 231) or orthopedic injury (OI, n = 146). Cognition was assessed using the NIH TB-CB at six and twelve months post-injury. We used linear mixed models to assess associations of injury group (TBI versus OI), timepoint (six versus twelve months), and the interaction of injury group and timepoint with NIH TB-CB Total Cognition, Fluid Cognition, and Crystallized Cognition composites, adjusted for sex and socioeconomic status (SES), with Bonferroni correction. We evaluated differences in cognition stratified by injury severity (complicated mild-moderate TBI vs severe TBI) using ANCOVA, adjusting for sex and SES. RESULTS: Neither injury group nor the interaction of group and timepoint were associated with Total (group: p = 0.50; timepoint*group: p = 0.185), Fluid (group: p = 0.297; timepoint*group: p = 0.842), or Crystallized Cognition (group: p = 0.039; timepoint*group: p = 0.017). However, children with severe TBI performed significantly worse on Fluid and Total Cognition than children with complicated mild-moderate TBI at six months (Fluid: p = 0.004, partial η(2) = 0.06, moderate effect, Total: p = 0.012 partial η(2) = 0.03, small-moderate effect) and twelve months post-injury (Fluid: p < 0.001, partial η(2) = 0.11, moderate-large effect, Total: p = 0.002, partial η(2) = 0.06, moderate effect). CONCLUSIONS: The NIH TB-CB detects worse cognitive functioning in children with severe TBI six-twelve months post-injury, largely driven by differences in Fluid Cognition. Our findings suggest the NIH TB-CB may be suitable for monitoring cognition in children with TBI.