title: Nine-year study of US high school soccer injuries: data from a national sports injury surveillance programme.
abstract: BACKGROUND
  Research on high school soccer injury epidemiology is sparse.
  
  
  OBJECTIVE
  To describe high school soccer injury rates, trends and patterns by type of athlete exposure (AE), position and sex.
  
  
  METHODS
  This descriptive epidemiological study used data from a large national high school sports injury surveillance programme to describe rates and patterns of soccer-related injuries including concussion sustained from 2005/2006 to 2013/2014. Injury rates are calculated per 1000 AEs.
  
  
  RESULTS
  Overall, 6154 soccer injuries occurred during 2 985 991 AEs; injury rate=2.06 per 1000 AEs. Injury rates were higher during competition (4.42) than practice (1.05; rate ratio (RR)=4.19; 95% CI 3.98 to 4.41), and in girls (2.33) than boys (1.83; RR=1.27, 95% CI 1.21 to 1.34). Boys' non-concussion injury rates decreased significantly (p=0.001) during the study period while reported concussion rates increased significantly (p=0.002). Girls' non-concussion rates were relatively stable and reported concussion rates increased significantly (p=0.004). Player-player contact was the injury mechanism that led to the most competition injuries (injury proportion ratio (IPR)=2.87; 95% CI 2.57 to 3.21), while non-contact injuries were the most common mechanisms among practice injuries (IPR=2.10; 95% CI 1.86 to 2.38). Recovery from concussion was >7 days in a third of the cases. Injury patterns were similar between sexes with respect to position played and location on the field at the time of injury.
  
  
  CONCLUSIONS
  High school soccer injury rates vary by sex and type of exposure, while injury patterns are more similar across sexes. Reported concussion rates increased significantly over the study period in male and female athletes.
authors.affiliation: Department of Family Medicine, University of Colorado School of Medicine, Denver, Colorado, USA.
authors.forename: Morteza
authors.initials: M
authors.lastname: Khodaee
authors.affiliation: Department of Epidemiology, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors.forename: Dustin W
authors.initials: DW
authors.lastname: Currie
authors.affiliation: Department of Family Medicine, Greenville Health System, University of South Carolina Greenville School of Medicine, Greenville, South Carolina, USA.
authors.forename: Irfan M
authors.initials: IM
authors.lastname: Asif
authors.affiliation: Department of Epidemiology, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.|Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA.
authors.forename: R Dawn
authors.initials: RD
authors.lastname: Comstock
mesh_terms: D000293:Adolescent; D056352:Athletes; D001265:Athletic Injuries / Q000145:classification / Q000453:epidemiology*; D001924:Brain Concussion / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D000068958:Return to Sport; D012574:Schools; D012737:Sex Factors; D012916:Soccer / Q000293:injuries*; D014481:United States
keywords: Injury; Sports; Surveillance