title: Annual and Seasonal Trends in Ambulatory Visits for Pediatric Concussion in Ontario between 2003 and 2013.
abstract: To investigate annual and seasonal trends in physician office and emergency department (ED) visit rates for pediatric concussion in Ontario between 2003 and 2013.
  
  
  
  A retrospective, population-based study was conducted using linked health administrative data from all concussion-related visits to ED and physician office by children aged 5 through 18 years. Time series analysis was used to assess whether periodic components exist in the monthly number of concussion-related visits.
  
  
  
  Over the 11-year study period, there were 176 685 pediatric visits for concussion in EDs and physician offices in Ontario. Standardized concussion-related visits showed a 4.4-fold (95% CI 4.37-4.45) increase per 100 000 from 2003 to 2013, with nearly 35 000 total visits in 2013. Concussion-related visits demonstrated a steep increase from 2010 onward. The greatest increases in standardized visits were in females (6.3-fold, 95% CI 6.23-6.46 vs 3.6-fold, 95% CI 3.56-3.64 in males) and 13-18.99 year olds (5.0-fold, 95% CI 4.93-5.08 vs 4.1-fold, 95% CI 3.99-4.27 in 9-12 years and 2.3-fold, 95% CI 2.23-2.42 in 5-8 years). A strong seasonal variability (R2autoreg = 0.87, P < .01) in the number of concussion-related visits was present, with most occurring in fall and winter.
  
  
  
  Pediatric concussion-related ED and physician office visit rates have greatly increased in the last decade, particularly since 2010. Prevention strategies may be targeted at those most at risk and at seasonal-related activities carrying the greatest risk of concussion.
authors.affiliation: Division of Pediatric Emergency Medicine, Department of Pediatrics, University of Ottawa, Ottawa, Ontario, Canada; Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada. Electronic address: rzemek@cheo.on.ca.
authors.forename: Roger L
authors.initials: RL
authors.lastname: Zemek
authors.affiliation: Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada.
authors.forename: Anne M
authors.initials: AM
authors.lastname: Grool
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.
authors.forename: Daniel
authors.initials: D
authors.lastname: Rodriguez Duque
authors.affiliation: School of Rehabilitation Science, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Carol
authors.initials: C
authors.lastname: DeMatteo
authors.affiliation: School of Kinesiology and Health Science, Faculty of Health, York University, Toronto, Ontario, Canada.
authors.forename: Linda
authors.initials: L
authors.lastname: Rothman
authors.affiliation: Children's Hospital of Eastern Ontario Research Institute, Ottawa, Ontario, Canada; Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, School of Epidemiology, Public Health and Preventive Medicine, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Eric I
authors.initials: EI
authors.lastname: Benchimol
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; Hospital for Sick Children, Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Astrid
authors.initials: A
authors.lastname: Guttmann
authors.affiliation: Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada; School of Kinesiology and Health Science, Faculty of Health, York University, Toronto, Ontario, Canada.
authors.forename: Alison K
authors.initials: AK
authors.lastname: Macpherson
mesh_terms: D000293:Adolescent; D000553:Ambulatory Care / Q000639:trends*; D001924:Brain Concussion / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D004636:Emergency Service, Hospital / Q000639:trends*; D005260:Female; D006801:Humans; D008297:Male; D009864:Ontario; D010372:Pediatrics; D012189:Retrospective Studies; D012621:Seasons
keywords: adolescents; children; concussion; emergency; epidemiology; mild traumatic brain injury; primary care