A-32 Multidimensionality of the SCAT-3 Symptom Evaluation Before and After Sport-Related Concussion

Abstract

Purpose To determine if a one- or four-factor model (i.e., cognitive, physical, affective, sleep-arousal) of post-concussion symptoms better fits the Sport Concussion Assessment Tool-3 (SCAT-3) Symptom Evaluation at baseline and post-injury time points. Methods Participants (N=24,696; 62.6% Male, 61.5% White, 9.2% Hispanic or Latino) were collegiate athletes from universities participating in the Concussion Assessment, Research, and Education Consortium. Student-athletes were given the SCAT-3 during a preseason baseline assessment, and four evaluations based on time since injury following concussion (i.e., 24-48 hours, asymptomatic, unrestricted return-to-play, and 6 months). A series of confirmatory factor analyses were used to test one- and four-factor models of the SCAT-3, using the Comparative Fit Index (CFI) to evaluate fit. A CFI ≥.95 indicated excellent fit and a difference in CFI≥.01 indicated superior fit during model comparison. Results The four-factor model showed superior fit at all time points compared to a one-factor model (One-factor: baseline=.89, 24-48 hours=.94, asymptomatic=.96, unrestricted return-to-play=.98, 6-months=.97; four-factor: baseline=.96, 24-48 hours=.97, asymptomatic=.98, unrestricted return-to-play=.99, 6-months=.99). Conclusions A multidimensional (i.e., four-factor) approach to the SCAT-3 Symptom Evaluation has a superior fit compared to a total score (i.e., one-factor) interpretation before and after injury. It is not yet clear how, or if, the four-factor model is beneficial in clinical settings for athletes with sport-related concussions. Symptom reporting is a large part of concussion assessment and return-to-play decisions, so future research should examine how concurrent relevant outcomes (i.e., neurocognitive performance, postural stability, long-term health, etc.) are related to symptom factor scores in comparison to total symptom scores.