174 Descriptive Epidemiology, Mechanisms, and Symptom Resolution of Concussion Sustained by National Collegiate Athletic Association Student Athletes, 2009/10 to 2013/14 Academic Years.

INTRODUCTION: Limited data exist on the epidemiology of concussions in collegiate student athletes. This study uses the National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) to describe the epidemiology of collegiate sports-related concussions (SRCs).

METHODS: We analyzed concussion data from samples of schools from 25 sports during the 2009/10 to 2013/14 academic years. We assessed incidence rates, injury mechanisms, symptomatology, and length of participation restriction.

RESULTS: During the 2009/10 to 2013/14 academic years, a total of 1670 concussions were reported, for an injury rate of 5.56/10 000 adverse events (AEs) (practice rate = 3.26/10 000AEs; competition rate = 14.59/10 000AEs). The largest concussion rates were in Men's Wrestling (10.92/10 000AEs; 95% CI 8.62-13.23), Men's Ice Hockey (7.91/10 000AEs; 95% CI 6.87-8.95), Women's Ice Hockey 23 (7.50/10 000AEs; 95% CI 5.91-9.10), and Men's Football (6.71/10 000AEs; 95% CI 6.17-7.24). However, Men's Football had the largest annual estimate of reported SRCs (3417), followed by Women's Soccer (1113) and Women's Basketball (998). Overall, more SRCs occurred in competitions (53.2%), although in all but 4 sports, more SRCs occurred in practices. The competition rate (12.81/10 000AEs) was 4.99 times the practice rate (2.57/10 000AEs; 95% CI 4.53-5.49). Of all the SRCs, 9.0% were recurrent. Most concussions were due to Player Contact (68.0%), followed by Surface Contact (12.6%), and Ball Contact (9.4%). Women had higher concussion rates than men in Soccer (P < .001), Basketball (P < .001), Lacrosse (P < .001), and Softball/Baseball (P = .01). An average 5.29 (SD = 2.94) concussion symptoms were reported, with the most common being headache (92.2%) and dizziness (68.9%). Additionally, 8.9% of concussions resulted in participation restriction for 4 weeks. The proportion of concussions requiring at least a week of participation restriction increased from 42.7% in 2009/10 to 70.2% in 2013/14 (Linear trend P < .001).

CONCLUSION: Concussion rates in collegiate athletes were highest during competition and among high-contact/collision sports. Rates were generally higher among women than men. Time trends in return to play time may indicate changing concussion management practices in which team medical staff are holding out players longer to ensure symptom resolution. Injury surveillance data can inform targeted interventions for concussion outcomes.