College of Public Health and Human Sciences

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, R(2) = 39%, R(2)(adj) = 34.2%, P < .001). Approximately 29% (R(2)(cv) = 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.