A Preliminary Formula to Predict Timing of Symptom Resolution for Collegiate Athletes Diagnosed With Sport Concussion

Abstract

Context Symptom presentation and recovery after sport concussion (SC) are variable. Empirically based models documenting typical symptom duration would assist health care providers in managing return to play after SC. Objective To develop a prediction model for SC symptom duration. Design Cross-sectional study. Setting Two National Collegiate Athletic Association Division I university laboratories. Patients or Other Participants Seventy-six (51 male and 25 female) concussed athletes with an average age of 19.5 ± 1.65 years who were evaluated within 24 hours of diagnosis. Intervention(s) Participants completed the Revised Head Injury Scale (HIS-r), Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT), and Sensory Organization Test within 24 hours of SC diagnosis. Main Outcome Measure(s) A stepwise multivariate regression incorporating ImPACT and Sensory Organization Test composites and HIS-r symptom severity-duration was used to predict the number of days athletes reported symptoms after SC. The resulting regression formula was cross-validated using the Stine cross-validation coefficient. Results The final formula consisted of the HIS-r's self-reported neck pain, drowsiness, tingling, and nervousness duration and ImPACT total symptom severity (R = 0.62, R2 = 39%, R2adj = 34.2%, P < .001). Approximately 29% (R2cv = 29%) of the variance associated with total days symptomatic after SC was explained by our preliminary formula when cross-validated. The current formula correctly identified 76% of participants who recovered within 10 days of injury. Conclusions Our results suggest that self-reported duration of 4 symptoms during the initial 24 hours after injury along with total symptom severity as measured by ImPACT accounted for a considerable amount of variance associated with days symptomatic after SC in collegiate athletes. Until the formula is cross-validated in a college-aged sample, caution is warranted in using it clinically.