title: Cyclist head and facial injury risk in relation to helmet fit: a case-control study.
abstract: BACKGROUND
  We examined the effect of bicycle helmet fit and position on head and facial injuries.
  
  
  METHODS
  Cases were helmeted cyclists with a head (n=297) or facial (n=289) injury. Controls were helmeted cyclists with other injuries, excluding the neck. Participants were interviewed in seven Alberta emergency departments or by telephone; injury data were collected from charts. Missing values were imputed using chained equations and custom prediction imputation models.
  
  
  RESULTS
  Compared with excellent helmet fit, those with poor fit had increased odds of head injury (odds ratio [OR] = 3.38, 95% confidence interval [CI]: 1.06-10.74). Compared with a helmet that stayed centred, those whose helmet tilted back (OR = 2.90, 95% CI: 1.54-5.47), shifted (OR = 1.91, 95% CI: 1.01-3.63) or came off (OR = 6.72, 95% CI: 2.86-15.82) had higher odds of head injury. A helmet that tilted back (OR = 4.81, 95% CI: 2.74-8.46), shifted (OR = 1.83, 95% CI: 1.04-3.19) or came off (OR = 3.31, 95% CI: 1.24-8.85) also increased the odds of facial injury.
  
  
  CONCLUSIONS
  Our findings have implications for consumer and retail education programs.
authors.affiliation: Department of Paediatrics, Faculty of Medicine, University of Calgary, Alberta Children's Hospital, Calgary, Alberta, Canada.
authors.forename: N R
authors.initials: NR
authors.lastname: Romanow
authors.affiliation: Department of Paediatrics, Faculty of Medicine, University of Calgary, Alberta Children's Hospital, Calgary, Alberta, Canada; Department of Community Health Sciences, Faculty of Medicine, University of Calgary, Alberta Children's Hospital, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute for Child and Maternal Health, University of Calgary, Calgary, Alberta, Canada.
authors.forename: B E
authors.initials: BE
authors.lastname: Hagel
authors.affiliation: Bachelor of Health Sciences Program, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Williamson
authors.affiliation: Department of Emergency Medicine and School of Public Health, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: B H
authors.initials: BH
authors.lastname: Rowe
mesh_terms: D000293:Adolescent; D000328:Adult; D000416:Alberta; D001642:Bicycling / Q000293:injuries*; D016022:Case-Control Studies; D002648:Child; D016001:Confidence Intervals; D003257:Consumer Product Safety; D006259:Craniocerebral Trauma / Q000453:epidemiology / Q000517:prevention & control*; D004636:Emergency Service, Hospital; D004867:Equipment Design; D005151:Facial Injuries / Q000453:epidemiology / Q000517:prevention & control*; D005260:Female; D006260:Head Protective Devices / Q000592:standards*; D006801:Humans; D015601:Injury Severity Score; D007407:Interviews as Topic; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D055815:Young Adult
keywords: bicycling; head protective devices; injuries