title: When the rules of the game are broken: what proportion of high school sports-related injuries are related to illegal activity?
abstract: OBJECTIVE
  To compare sport and gender differences in injury rates and proportions of injuries related to illegal activity and to describe the epidemiology of injuries related to illegal activity.
  
  
  METHODS
  Descriptive epidemiology study.
  
  
  METHODS
  100 US high schools.
  
  
  METHODS
  Athletes participating in nine sports: boys' football, soccer, basketball, wrestling, and baseball plus girls' soccer, volleyball, basketball, and softball.
  
  
  METHODS
  Illegal activity-related injuries were analyzed using data from the 2005-06 and 2006-07 National High School Sports-Related Injury Surveillance Study.
  
  
  RESULTS
  Nationally, an estimated 98 066 injuries were directly related to an action that was ruled illegal activity by a referee/official or disciplinary committee, giving an injury rate of 0.24 injuries per 1000 athletic competition-exposures. Boys' and girls' soccer had the highest rates of injuries related to illegal activity, and girls' volleyball, girls' softball, and boys' baseball had the lowest. Overall, 6.4% of all high school sports-related injuries were related to illegal activity, with the highest proportion in girls' basketball (14.0%), girls' soccer (11.9%), and boys' soccer (11.4%). A greater proportion of injuries related to illegal activity were to the head/face (32.3%) and were concussions (25.4%) than injuries not related to illegal activity (13.8% (injury proportion ratio 2.35; 95% CI 1.82 to 3.04; p<0.001) and 10.9% (injury proportion ratio 2.35; 95% CI 1.71 to 3.22; p<0.001), respectively).
  
  
  CONCLUSIONS
  Illegal activity is an overlooked risk factor for sports-related injury. Reducing illegal activity through enhanced enforcement of sports' rules and targeted education about the dangers of illegal activity for players, coaches, and referees/officials may reduce sports-related injuries.
authors.affiliation: The Research Institute at Nationwide Children's Hospital, Center for Injury Research and Policy, Columbus, OH 43205, USA. christy.collins@nationwidechildrens.org
authors.forename: C L
authors.initials: CL
authors.lastname: Collins
authors.forename: S K
authors.initials: SK
authors.lastname: Fields
authors.forename: R D
authors.initials: RD
authors.lastname: Comstock
mesh_terms: D000293:Adolescent; D001265:Athletic Injuries / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D003617:Dangerous Behavior; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D040242:Risk Reduction Behavior; D017678:Sex Distribution; D012737:Sex Factors; D014481:United States / Q000453:epidemiology