title: Incidence of sports-related concussion among youth football players aged 8-12 years.
abstract: OBJECTIVE
  To determine the risk of concussion among youth football players (ages 8-12 years).
  
  
  METHODS
  Participants included 468 male youth football players in western Pennsylvania during the 2011 youth football season. Incidence rates (IRs) and incidence density ratios (IDRs) of concussion were calculated for games and practices and for age groups.
  
  
  RESULTS
  There was a total of 11,338 (8415 practice and 2923 game) athletic exposures (AEs) in the study period, during which 20 medically diagnosed concussions occurred. A majority of concussions were the result of head-to-head (45%) contact. The combined concussion IR for practices and games was 1.76 per 1000 AEs (95% CI 0.99-2.54). The concussion IR was 0.24 per 1000 AEs (95% CI 0.04-0.79) in practices and 6.16 per 1000 AEs (95% CI 3.76-9.54) in games. The IDR for concussions in games to practices was 25.91 (95% CI 6.01-111.70). The IDR of concussions for youth aged 11-12 years compared with youth aged 8-10 years was 2.72 (95% CI 0.66-4.78).
  
  
  CONCLUSIONS
  The overall IR for concussion in youth football players aged 8-12 years was comparable with that reported previously for high school and collegiate samples. However, participation in games was associated with an increase in risk of concussion compared with practices, which was higher than rates previously reported for high school and collegiate athletes. Younger players were slightly less likely to incur a concussion than were older players.
authors.affiliation: Department of Orthopaedic Surgery/University of Pittsburgh Medical Center Sports Medicine Concussion Program, University of Pittsburgh, Pittsburgh, PA, USA. akontos@pitt.edu
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Kontos
authors.forename: R J
authors.initials: RJ
authors.lastname: Elbin
authors.forename: Vanessa C
authors.initials: VC
authors.lastname: Fazio-Sumrock
authors.forename: Scott
authors.initials: S
authors.lastname: Burkhart
authors.forename: Hasani
authors.initials: H
authors.lastname: Swindell
authors.forename: Joseph
authors.initials: J
authors.lastname: Maroon
authors.forename: Michael W
authors.initials: MW
authors.lastname: Collins
mesh_terms: D000367:Age Factors; D001924:Brain Concussion / Q000453:epidemiology* / Q000209:etiology; D002648:Child; D005538:Football / Q000293:injuries*; D006801:Humans; D015994:Incidence; D008297:Male; D010414:Pennsylvania / Q000453:epidemiology; D011446:Prospective Studies; D012307:Risk Factors
keywords: AE; Athletic exposure; CDC; Centers for Disease Control and Prevention; IDR; IR; Incidence density ratio; Incidence rate