title: Mild traumatic brain injury in the United States, 1998--2000.
abstract: OBJECTIVE
  To determine the incidence and epidemiology of emergency department (ED)-attended mild traumatic brain injury (mTBI) in the US.
  
  
  METHODS
  Secondary analysis of ED visits for mTBI in the National Hospital Ambulatory Medical Care Survey for 1998--2000.
  
  
  METHODS
  MTBI defined by International Classification of Diseases, 9th Revision, Clinical Modification (ICD9-CM) codes for 'skull fracture', 'concussion', 'intracranial injury of unspecified nature' and 'head injury, unspecified'.
  
  
  RESULTS
  The average incidence of mTBI was 503.1/100000, with peaks among males (590/100000), American Indians/Alaska Natives (1,026/100000) and those <5 years of age (1,115.2/100000). MTBI incidence was highest in the Midwest region (578.4/10000) and in non-urban areas (530.9/100000) of the US. Bicycles and sports accounted for 26.4% of mTBI in the 5-14 age group.
  
  
  CONCLUSIONS
  The national burden of mTBI is significant and the incidence higher than that reported by others. Possible explanations are discussed. Bicycle and sports-related injuries are an important and highly preventable cause of mTBI underscoring the need to promote prevention programmes on a national level.
authors.affiliation: Department of Emergency Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA. jeff_bazarian@urmc.rochester.edu
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Bazarian
authors.forename: Jason
authors.initials: J
authors.lastname: McClung
authors.forename: Manish N
authors.initials: MN
authors.lastname: Shah
authors.forename: Yen Ting
authors.initials: YT
authors.lastname: Cheng
authors.forename: William
authors.initials: W
authors.lastname: Flesher
authors.forename: Jess
authors.initials: J
authors.lastname: Kraus
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001265:Athletic Injuries / Q000453:epidemiology; D001930:Brain Injuries / Q000453:epidemiology* / Q000208:ethnology / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004630:Emergencies / Q000453:epidemiology; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D007198:Indians, North American / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D017678:Sex Distribution; D014481:United States / Q000453:epidemiology