title: The Incidence of Postconcussion Syndrome Remains Stable Following Mild Traumatic Brain Injury in Children.
abstract: BACKGROUND
  Improving our knowledge about the natural history and persistence of symptoms following mild traumatic brain injury is a vital step in improving the provision of health care to children with postconcussion syndrome. The purposes of this study were to (1) determine the incidence and persistence of symptoms after mild traumatic brain injury and (2) ascertain whether Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), symptom criteria for postconcussion syndrome in adults are appropriate for use in children.
  
  
  METHODS
  A tertiary care pediatric emergency department was the setting for this study. This was a prospective observational follow-up cohort study of children (ages 2 to 18 years) with mild traumatic brain injury. Data were collected in person during the acute presentation, and subsequent follow-up was performed by telephone at 7-10 days and 1, 2, and 3 months postinjury. Postconcussion Symptom Inventory for parents and children was used. The DSM-IV diagnostic criteria for postconcussion syndrome were explored using receiver operating characteristic curve analysis.
  
  
  RESULTS
  A total of 467 children (62.5% boys, median age 12.04, range 2.34-18.0) with mild traumatic brain injury participated. The median time until symptom resolution was 29.0 days (95% confidence intervals: 26.09-31.91). Three months after injury, 11.8% of children with mild traumatic brain injury remained symptomatic. Receiver operating curve characteristic analysis of the postconcussion syndrome criteria successfully classified symptomatic participants at three months postinjury; the adolescent receiver operating characteristic curve was excellent with the area under the curve being 0.928 (P < 0.001, standard error 0.019).
  
  
  CONCLUSIONS
  Consistent with our previous study, 11.8% of children presenting to the emergency room with a mild traumatic brain injury remain symptomatic at 3 months postinjury. This is the first study to demonstrate stable incidence rates of postconcussion syndrome in children and that modified DSM-IV criteria can be used to successfully classify postconcussion syndrome in children. Although most children report a decay in symptoms over time, 10% of children develop symptoms even though they initially had a good outcome. Caution should be used when using only parent report as a surrogate for childhood outcomes following a concussion.
authors.affiliation: Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta. Electronic address: karen.barlow@albertahealthservices.ca.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Barlow
authors.affiliation: Alberta Health Services, Calgary, Alberta.
authors.forename: Susan
authors.initials: S
authors.lastname: Crawford
authors.affiliation: Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta; Alberta Children's Hospital, Calgary, Alberta.
authors.forename: Brian L
authors.initials: BL
authors.lastname: Brooks
authors.affiliation: Alberta Children's Hospital, Calgary, Alberta.
authors.forename: Brenda
authors.initials: B
authors.lastname: Turley
authors.affiliation: Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta.
authors.forename: Angelo
authors.initials: A
authors.lastname: Mikrogianakis
mesh_terms: D000293:Adolescent; D000416:Alberta / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D038223:Post-Concussion Syndrome / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology
keywords: concussion; diagnostic criteria; incidence; mild traumatic brain injury; postconcussion syndrome