title: Bicycle helmet prevalence two years after the introduction of mandatory use legislation for under 18 year olds in Alberta, Canada.
abstract: OBJECTIVE
  To determine changes in helmet use in cyclists following the introduction of a bicycle helmet law for children under age 18.
  
  
  METHODS
  Cyclists were observed by two independent observers from July to August 2004 (post-legislation) in Edmonton, Alberta. The data were compared with a similar survey completed at the same locations and days in July to August 2000 (pre-legislation). Data were collected for 271 cyclists in 2004 and 699 cyclists in 2000.
  
  
  RESULTS
  The overall prevalence of helmet use increased from 43% (95% CI 39 to 47%) in 2000 to 53% (95% CI 47 to 59%) in 2004. Helmet use increased in those under 18, but did not change in those 18 and older. In the cluster adjusted multivariate Poisson regression model, the prevalence of helmet use significantly increased for those under age 18 (adjusted prevalence ratio (APR) 3.69, 95% CI 2.65 to 5.14), but not for those 18 years and older (APR 1.17, 95% CI 0.95 to 1.43).
  
  
  CONCLUSIONS
  Extension of legislation to all age groups should be considered.
authors.affiliation: Department of Paediatrics, Faculty of Medicine, University of Calgary, Alberta Children's Hospital, Calgary, Alberta, Canada. brent.hagel@calgaryhealthregion.ca
authors.forename: B E
authors.initials: BE
authors.lastname: Hagel
authors.forename: J W
authors.initials: JW
authors.lastname: Rizkallah
authors.forename: A
authors.initials: A
authors.lastname: Lamy
authors.forename: K L
authors.initials: KL
authors.lastname: Belton
authors.forename: G S
authors.initials: GS
authors.lastname: Jhangri
authors.forename: N
authors.initials: N
authors.lastname: Cherry
authors.forename: B H
authors.initials: BH
authors.lastname: Rowe
mesh_terms: D000293:Adolescent; D000416:Alberta; D001642:Bicycling / Q000331:legislation & jurisprudence* / Q000639:trends; D002648:Child; D002675:Child, Preschool; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D005260:Female; D006260:Head Protective Devices / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male