Estimating Concussion Incidence Using Sports Injury Surveillance Systems: Complexities and Potential Pitfalls

Numerous sports injury surveillance systems exist with the capability of tracking concussion incidence data. It is important for the consumers of sport-related concussion data, be they researchers or the public, to have a comprehensive understanding of the strengths and limitations of sports injury surveillance systems. This article discusses issues of system design and analysis that affect the interpretation and understanding of sport-related concussion incidence data from sports injury surveillance systems. Such understanding will help inform the design of sports injury surveillance systems and research studies that aim to identify risk factors, develop prevention strategies, and evaluate prevention mechanisms

The first decade of web-based sports injury surveillance: Descriptive epidemiology of injuries in US high school boys' ice hockey (2008-2009 through 2013-2014) and National Collegiate Athletic Association men's and women's ice hockey (2004-2005 through 2013-2014)

Context: Web-based sports injury surveillance via programs such as the High School Reporting Information Online system and the National Collegiate Athletic Association Injury Surveillance Program has aided efforts to collect data on ice hockey injuries. Objective: To describe the epidemiology of injuries sustained in high school boy's ice hockey in the 2008-2009 through 2013-2014 academic years and collegiate men's and women's ice hockey in the 2004-2005 through 2013-2014 academic years using Web-based surveillance. Design: Descriptive epidemiology study. Setting: Online injury surveillance of ice hockey teams of high school boys (annual average ¼ 34), collegiate men (annual average ¼ 20), and collegiate women (annual average ¼ 11). Patients or Other Participants: Boys', men's, and women's ice hockey players who participated in practices and competitions during the 2008-2009 through 2013-2014 high school academic years or the 2004-2005 through 2013-2014 collegiate academic years. Main Outcome Measure(s): Athletic trainers collected time-loss (24 hours) injury and exposure data. We calculated injury rates per 1000 athlete-exposures (AEs), injury rate ratios (IRRs) with 95% confidence intervals (CIs), and injury proportions by body site and diagnosis. Results: The High School Reporting Information Online system documented 831 boys' ice hockey time-loss injuries during 356 997 AEs; the National Collegiate Athletic Association Injury Surveillance Program documented 2611 men's ice hockey time-loss injuries during 552 642 AEs and 752 women's ice hockey injuries during 232 051 AEs. Injury rates were higher in collegiate men than in high school boys during 2008-2009 through 2013-2014 (4.38 versus 2.33/1000 AEs; IRR ¼ 1.88; 95% CI ¼ 1.73, 2.05) and collegiate women during 2004-2005 through 2013-2014 (IRR ¼ 1.46; 95% CI ¼ 1.34, 1.58). Most injuries occurred during competitions (boys ¼ 80.0%, men ¼ 66.9%, women ¼ 55.3%); injury rates were higher in competitions than in practices for boys (IRR ¼ 8.14; 95% CI ¼ 6.87, 9.65), men (IRR ¼ 6.58; 95% CI ¼ 6.06, 7.13), and women (IRR ¼ 3.63; 95% CI ¼ 3.14, 4.19). At all levels, most injuries occurred to the head/face and shoulder/clavicle and resulted in concussions, contusions, or ligament sprains. Conclusions: Injury rates varied across sports but were consistently higher in competitions than in practices. In competitions, concussions were common injuries, highlighting the need for continued development of injury-prevention strategies

The first decade of web-based sports injury surveillance: Descriptive epidemiology of injuries in us high school girls' volleyball (2005-2006 through 2013-2014) and national collegiate athletic association women's volleyball (2004-2005 Through 2013-2014)

Context: The advent of Web-based sports injury surveillance via programs such as the High School Reporting Information Online system and the National Collegiate Athletic Association Injury Surveillance Program has aided in the acquisition of girls' and women's volleyball injury data. Objective: To describe the epidemiology of injuries sustained in high school girls' volleyball in the 2005-2006 through 2013-2014 academic years and collegiate women's volleyball in the 2004-2005 through 2013-2014 academic years using Webbased sports injury surveillance. Design: Descriptive epidemiology study. Setting: Online injury surveillance from high school girls' (annual average=100) and collegiate women's (annual average = 50) volleyball teams. Patients or Other Participants: Girls' and women's volleyball players who participated in practices and competitions during the 2005-2006 through 2013-2014 academic years in high school and the 2004-2005 through 2013-2014 academic years in college. Main Outcome Measure(s): Athletic trainers collected timeloss (≥24 hours) injury and exposure data. Injury rates per 1000 athlete-exposures (AEs), injury rate ratios (IRRs) with 95% confidence intervals (CIs), and injury proportions by body site and diagnosis were calculated. Results: The High School Reporting Information Online system documented 1634 time-loss injuries during 1 471 872 AEs; the National Collegiate Athletic Association Injury Surveillance Program documented 2149 time-loss injuries during 563 845 AEs. The injury ratewas higher in college than in high school (3.81/ 1000 versus 1.11/1000 AEs; IRR=3.43; 95%CI=3.22, 3.66), and higher in high schools with ≤1000 students than in those with >1000 students (IRR=1.35; 95% CI=1.23, 1.49). Injury rates did not vary by collegiate division. The injury rate was higher during competitions than practices for high school (IRR=1.23; 95% CI= 1.12, 1.36) but not for college (IRR= 1.01; 95% CI= 0.92, 1.10). Ankle sprains were common in both the high school and collegiate setting. However, liberos had a high incidence of concussion. Conclusions: Injury rates were higher among collegiate than high school players. However, injury rates differed by event type in high school, unlike college. Concussion injury patterns among liberos varied from those for other positions. These findings highlight the need for injury-prevention interventions specific to setting and position

The first decade of web-based sports injury surveillance: Descriptive epidemiology of injuries in US high school boys' wrestling (2005-2006 through 2013-2014) and National Collegiate Athletic Association Men's Wrestling (2004-2005 through 2013-2014)

Context: The advent of Web-based sports injury surveillance via programs such as the High School Reporting Information Online system and the National Collegiate Athletic Association Injury Surveillance Program has aided the acquisition of wrestling injury data. Objective: To describe the epidemiology of injuries sustained in high school boys' wrestling in the 2005-2006 through 2013-2014 academic years and collegiate men's wrestling in the 2004-2005 through 2013-2014 academic years using Web-based sports injury surveillance. Design: Descriptive epidemiology study. Setting: Online injury surveillance from wrestling teams of high school boys (annual average ¼ 100) and collegiate men (annual average ¼ 11). Patients or Other Participants: Male wrestlers who participated in practices and competitions during the 2005-2006 through 2013-2014 academic years in high school or the 2004-2005 through 2013-2014 academic years in college. Main Outcome Measure(s): Athletic trainers collected time-loss (24 hours) injuries and exposure data during this time period. Injury rates per 1000 athlete-exposures (AEs), injury rate ratios with 95% confidence intervals, and injury proportions by body site and diagnosis were calculated. Results: The High School Reporting Information Online documented 3376 time-loss injuries during 1 416 314 AEs; the National Collegiate Athletic Association Injury Surveillance Program documented 2387 time-loss injuries during 257 297 AEs. The total injury rate was higher in college than in high school (9.28 versus 2.38/1000 AEs; injury rate ratio ¼ 3.89; 95% confidence interval ¼ 3.69, 4.10). In high school, the most commonly injured body parts for both practices and competitions were the head/face (practices ¼ 19.9%, competitions ¼ 21.4%) and shoulder/clavicle (practices ¼ 14.1%, competitions ¼ 21.0%). In college, the most frequently injured body parts for both practices and competitions were the knee (practices ¼ 16.7%, competitions ¼ 30.4%) and head/face (practices ¼ 12.1%, competitions ¼ 14.6%). Conclusions: Injury rates were higher in collegiate than in high school players, and the types of injuries sustained most often differed. Based on these results, continued study of primary and secondary prevention of injury in wrestlers across levels of competition is warranted

The first decade of web-based sports injury surveillance: Descriptive epidemiology of injuries in United States high school football (2005-2006 through 2013-2014) and National collegiate athletic association football (2004-2005 through 2013-2014)

Context: The advent of Web-based sports injury surveillance via programs such as the High School Reporting Information Online system and the National Collegiate Athletic Association Injury Surveillance Program has aided the acquisition of football injury data. Objective: To describe the epidemiology of injuries sustained in high school football in the 2005-2006 through 2013-2014 academic years and collegiate football in the 2004-2005 through 2013-2014 academic years using Web-based sports injury surveillance. Design: Descriptive epidemiology study. Setting: Online injury surveillance from football teams of high school boys (annual average ¼ 100) and collegiate men (annual average ¼ 43). Patients or Other Participants: Football players who participated in practices and competitions during the 2005-2006 through 2013-2014 academic years in high school or the 2004-2005 through 2013-2014 academic years in college. Main Outcome Measure(s): Athletic trainers collected time-loss injury (24 hours) and exposure data. Injury rates per 1000 athlete-exposures (AEs), injury rate ratios (IRRs) with 95% confidence intervals (CIs), and injury proportions by body site and diagnosis were calculated. Results: The High School Reporting Information Online system documented 18 189 time-loss injuries during 4 539 636 AEs; the National Collegiate Athletic Association Injury Surveillance Program documented 22 766 time-loss injuries during 3 121 476 AEs. The injury rate was higher among collegiate than high school (7.29 versus 4.01/1000 AEs; IRR ¼ 1.82; 95% CI ¼ 1.79, 1.86) athletes. Most injuries occurred during competitions in high school (53.2%) and practices in college (60.9%). The competition injury rate was higher than the practice injury rate among both high school (IRR ¼ 5.62; 95% CI ¼ 5.46, 5.78) and collegiate (IRR ¼ 6.59; 95% CI ¼ 6.41, 6.76) players. Most injuries at both levels affected the lower extremity and the shoulder/clavicle and were diagnosed as ligament sprains and muscle/tendon strains. However, concussion was a common injury during competitions among most positions. Conclusions: Injury rates were higher in college than in high school and higher for competitions than for practices. Concussion was a frequent injury sustained during competitions, which confirms the need to develop interventions to mitigate its incidence and severity

The first decade of web-based sports injury surveillance: Descriptive epidemiology of injuries in US high school girls’ softball (2005–2006 through 2013–2014) and National Collegiate Athletic Association women’s softball (2004–2005 through 2013–2014)

Context: The advent of Web-based sports injury surveillance via programs such as the High School Reporting Information Online system and the National Collegiate Athletic Association Injury Surveillance Program has aided the acquisition of girls’ and women’s softball injury data. Objective: To describe the epidemiology of injuries sustained in high school girls’ softball in the 2005–2006 through 2013–2014 academic years and collegiate women’s softball in the 2004–2005 through 2013–2014 academic years using Web-based sports injury surveillance. Design: Descriptive epidemiology study. Setting: Online injury surveillance from softball teams in high school girls (annual average ¼ 100) and collegiate women (annual average ¼ 41). Patients or Other Participants: Girls’ or women’s softball players who participated in practices and competitions during the 2005–2006 through 2013–2014 academic years in high school and the 2004–2005 through 2013–2014 academic years in college. Main Outcome Measure(s): Athletic trainers collected time-loss injury and exposure data. Injury rates per 1000 athlete-exposures (AEs) were calculated. Injury rate ratios (IRRs) with 95% confidence intervals (CIs) compared injury rates by competition level, school size or division, event type, and time in season. Results: The High School Reporting Information Online system documented 1357 time-loss injuries during 1 173 722 AEs; the National Collegiate Athletic Association Injury Surveillance Program documented 1848 time-loss injuries during 579 553 AEs. The injury rate was higher in college than in high school (3.19 versus 1.16/1000 AEs; IRR ¼ 2.76; 95% CI ¼ 2.57, 2.96). The competition injury rate was higher than the practice injury rate in high school (IRR ¼ 2.02; 95% CI ¼ 1.82, 2.25) and in college (IRR ¼ 1.39; 95% CI ¼ 1.27, 1.52). Softball players at both levels sustained a variety of injuries, with the most common being ankle sprains and concussions. Many injuries also occurred while fielding or running bases. Conclusions: Injury rates were greater in collegiate versus high school softball and in competitions versus practices. These findings highlight the need for injury-prevention interventions, including strength-training and prevention programs to reduce ankle sprains and provide protection for batters from pitches and fielders from batted balls

The first decade of web-based sports injury surveillance: Descriptive epidemiology of injuries in US high school boys’ baseball (2005–2006 through 2013–2014) and National Collegiate Athletic Association men’s baseball (2004–2005 through 2013–2014)

Context: The advent of Web-based sports injury surveillance via programs such as the High School Reporting Information Online system and the National Collegiate Athletic Association Injury Surveillance Program has aided the acquisition of boys’ and men’s baseball injury data. Objective: To describe the epidemiology of injuries sustained in high school boys’ baseball in the 2005–2006 through 2013–2014 academic years and collegiate men’s baseball in the 2004–2005 through 2013–2014 academic years using Web-based sports injury surveillance. Design: Descriptive epidemiology study. Setting: Online injury surveillance from baseball teams in high school boys (annual average ¼ 100) and collegiate men (annual average ¼ 34). Patients or Other Participants: Boys’ or men’s baseball players who participated in practices and competitions during the 2005–2006 through 2013–2014 academic years in high school or the 2004–2005 through 2013–2014 academic years in college, respectively. Main Outcome Measure(s): Athletic trainers collected time-loss injury and exposure data. Injury rates per 1000 athlete-exposures (AEs) were calculated. Injury rate ratios (IRRs) with 95% confidence intervals (CIs) compared injury rates by schoolsize or division, time in season, event type, and competition level. Results: The High School Reporting Information Online system documented 1537 time-loss injuries during 1 573 257 AEs; the National Collegiate Athletic Association Injury Surveillance Program documented 2574 time-loss injuries during 804 737 AEs. The injury rate was higher in college than in high school (3.20 versus 0.98/1000 AEs; IRR ¼ 3.27; 95% CI ¼ 3.07, 3.49). The competition injury rate was higher than the practice injury rate in high school (IRR ¼ 2.27; 95% CI ¼ 2.05, 2.51) and college (IRR ¼ 2.32; 95% CI ¼ 2.15, 2.51). Baseball players at the high school and collegiate levels sustained a variety of injuries across the body, with the most common injuries reported to the upper extremity. Many injuries also occurred while fielding or pitching. Conclusions: Injury rates were greater in collegiate versus high school baseball and in competition versus practice. These findings highlight the need for injury-prevention interventions focused on reducing the incidence of upper extremity injuries and protecting batters from pitches and fielders from batted balls

The first decade of web-based sports injury surveillance: Descriptive epidemiology of injuries in US high school boys' soccer (2005-2006 through 2013-2014) and national collegiate athletic association men's soccer (2004-2005 through 2013-2014)

Context: The advent of Web-based sports injury surveillance via programs such as the High School Reporting Information Online system and the National Collegiate Athletic Association Injury Surveillance Program has aided the acquisition of boys' and men's soccer injury data. Objective: To describe the epidemiology of injuries sustained in high school boys' soccer in the 2005-2006 through 2013-2014 academic years and collegiate men's soccer in the 2004-2005 through 2013-2014 academic years using Web-based sports injury surveillance. Design: Descriptive epidemiology study. Setting: Online injury surveillance from soccer teams of high school boys (annual average ¼ 100) and collegiate men (annual average ¼ 41). Patients or Other Participants: Boys' or men's soccer players who participated in practices and competitions during the 2005-2006 through 2013-2014 academic years in high school and the 2004-2005 through 2013-2014 academic years in college, respectively. Main Outcome Measure(s): Athletic trainers collected time-loss (24 hours) injury and exposure data. Injury rates per 1000 athlete-exposures (AEs), injury rate ratios (IRRs) with 95% confidence intervals (CIs), and injury proportions by body site and diagnosis were calculated. Results: High School Reporting Information Online documented 2912 time-loss injuries during 1 592 238 AEs; the National Collegiate Athletic Association Injury Surveillance Program documented 4765 time-loss injuries during 686 918 AEs. The injury rate was higher in college than in high school (6.94 versus 1.83/1000 AEs; IRR ¼ 3.79; 95% CI ¼ 3.62, 3.97). Injury rates increased with smaller school size for high schools and were higher in Division I than in Divisions II and III. The injury rate was higher during competitions than during practices in both high school (IRR ¼ 3.55; 95% CI ¼ 3.30, 3.83) and college (IRR ¼ 3.45; 95% CI ¼ 3.26, 3.65). Most injuries were to the lower extremity. However, concussion was a common injury, particularly in collegiate goalkeepers and at all positions for high school players. Concussions accounted for more than one-fifth of injuries in high school games. Conclusions: Injury-prevention interventions should be tailored to reflect variations in the incidence and type of injury by level of competition, event type, and position

The first decade of web-based sports injury surveillance: Descriptive epidemiology of injuries in US high school girls’ basketball (2005–2006 through 2013–2014) and National Collegiate Athletic Association women’s basketball (2004–2005 through 2013–2014)

Context: The advent of Web-based sports injury surveillance via programs such as the High School Reporting Information Online system and the National Collegiate Athletic Association Injury Surveillance Program has aided the acquisition of girls’ and women’s basketball injury data. Objective: To describe the epidemiology of injuries sustained in high school girls’ basketball in the 2005–2006 through 2013–2014 academic years and collegiate women’s basketball in the 2004–2005 through 2013–2014 academic years using Web-based sports injury surveillance. Design: Descriptive epidemiology study. Setting: Online injury surveillance from basketball teams in high school girls (annual average ¼ 100) and collegiate women (annual average ¼ 57). Patients or Other Participants: Girls’ and women’s basketball players who participated in practices and competitions during the 2005–2006 through 2013–2014 academic years in high school or the 2004–2005 through 2013–2014 academic years in college. Main Outcome Measure(s): Certified athletic trainers collected time-loss (24 hours) injury and exposure data. Injury rates per 1000 athlete-exposures (AEs) were calculated. Injury rate ratios (IRRs) with 95% confidence intervals (CIs) were used to compare injury rates by school size or division, time in season, event type, and competition level. Results: The High School Reporting Information Online system documented 2930 time-loss injuries during 1 609 733 AEs; the National Collegiate Athletic Association Injury Surveillance Program documented 3887 time-loss injuries during 783 600 AEs. The injury rate was higher in college than in high school (4.96 versus 1.82/1000 AEs; IRR ¼ 2.73; 95% CI ¼ 2.60, 2.86). The injury rate was higher in competitions than in practices for both high school (IRR ¼ 3.03; 95% CI ¼ 2.82, 3.26) and collegiate (IRR ¼ 1.99; 95% CI ¼ 1.86, 2.12) players. The most common injuries at both levels were ligament sprains, concussions, and muscle/tendon strains; the majority of injuries affected the ankle, knee, and head/face. These injuries were often caused by contact with another player or a noncontact mechanism. Conclusions: Injury rates were higher in collegiate than in high school athletes and in competitions than in practices. Similarities in distributions of injuries by body parts, specific diagnoses, and mechanisms of injury suggest that both levels may benefit from similar injury-prevention strategies

The first decade of web-based sports injury surveillance: Descriptive epidemiology of injuries in US high school girls' lacrosse (2008-2009 through 2013-2014) and National Collegiate Athletic Association women's lacrosse (2004-2005 through 2013-2014)

Context: The advent of Web-based sports injury surveillance via programs such as the High School Reporting Information Online (HS RIO) system and the National Collegiate Athletic Association Injury Surveillance Program (NCAA-ISP) has aided the acquisition of girls' and women's lacrosse injury data. Objective: To describe the epidemiology of injuries sustained in high school girls' lacrosse in the 2008-2009 through 2013-2014 academic years and collegiate women's lacrosse in the 2004-2005 through 2013-2014-academic years using Web-based sports injury surveillance. Design: Descriptive epidemiology study. Setting: Online injury surveillance from high school girls' (annual average ¼ 55) and collegiate women's (annual average ¼ 19) lacrosse teams. Patients or Other Participants: Female lacrosse players who participated in practices or competitions during the 2008-2009 through 2013-2014 academic years for high school or the 2004-2005 through 2013-2014 academic years for college. Main Outcome Measure(s): Athletic trainers collected time-loss injury (24 hours) and exposure data. We calculated injury rates per 1000 athlete-exposures (AEs), injury rate ratios (IRRs) with 95% confidence intervals (CIs), and injury proportions by body site and diagnosis. Results: High school RIO documented 700 time-loss injuries during 481 687 AEs; the NCAA-ISP documented 1027 time-loss injuries during 287 856 AEs. The total injury rate during 2008-2009 through 2013-2014 was higher in college than in high school (2.55 versus 1.45/1000 AEs; IRR ¼ 1.75; 95% CI ¼ 1.54, 1.99). Most injuries occurred during competitions in high school (51.1%) and practices in college (63.8%). Rates were higher during competitions compared with practices in high school (IRR ¼ 2.32; 95% CI ¼ 2.00, 2.69) and college (IRR ¼ 2.38; 95% CI ¼ 2.09, 2.70). Concussion was the most common diagnosis among all high school and most collegiate player positions, and the main mechanism of contact was with a playing apparatus (eg, stick, ball). Ligament sprains were also common (HS RIO practices ¼ 22.2%, competitions ¼ 30.3%; NCAA-ISP practices ¼ 25.5%, competitions ¼ 30.9%). Conclusions: Rates of injury were higher in college versus high school female lacrosse players and in competitions versus practices. Injury-prevention strategies are essential to decrease the incidence and severity of concussions and ligament sprains