Time Trends in Incidence and Severity of Injury among NCAA Soccer Players, 1990-1996 and 2004-2009

BACKGROUND: A number of socio-cultural and environmental changes have occurred over the past several decades that may affect the risk of injury among young athletes playing soccer. PURPOSE: To identify trends in injury incidence and severity between two time periods (1990-1996 and 2004-2009) in both male and female NCAA soccer players. METHODS: Data were analyzed from the National Collegiate Athletic Association (NCAA) Injury Surveillance System (ISS). As per the data collection guidelines, injury incidence was defined as: 1) any injury event that occurred during participation in an intercollegiate game or practice; 2) that required medical attention; and 3) restricted participation or performance for \u3e1 day beyond the event. To account for varying levels of playing exposure and contribution to injury occurrence among the athletes, we calculated Athlete-Exposure (AE), defined as a single athlete participating in a single practice or competition with any probability of injury. Incidence density (ID) then was calculated as the number of events per 1000 AE within each time period. The rate ratio (RR), along with the 95% Wald confidence interval (CI), compared incidence density in 2004-2009 relative to that in 1990-1996. RESULTS: Overall sex-pooled injury rates were significantly lower in the 2004-2009 cohort compared with the 1990-1996 cohort [RR=0.88 (95%CI=0.86, 0.91)] and this was true for almost every category of injury studied. The lower rates were especially noticeable for recurrent injuries [RR=0.62 (95%CI=0.57, 0.68)], short-term injuries [RR=0.69 (95%CI=0.67, 0.72)] and for injuries requiring surgery [RR=0.35 (95%CI=0.29, 0.41)]. There was also a significant reduction in injuries occurring during games, particularly for injuries occurring during the second half [RR=0.69 (95%CI: 0.66, 0.73)]. In contrast, we observed a significant increase in rates of long-term (\u3e7 days pf lost time) injuries between 1990-1996 and 2004-2009 [RR=1.33 (95%CI=1.27, 1.40)]. CONCLUSIONS: These surveillance data show decreasing trends in collegiate soccer injuries. Whether these decreases are attributable to greater resources being allocated toward athlete health, injury management, or toward the safety of the playing environment cannot be determined. Given the prominence of soccer play in the United States, public health efforts should promote the use of this surveillance system to better inform and evaluate injury prevention practices and policies directed toward player safety