title: Concordance between childhood injury diagnoses from two sources: an injury surveillance system and a physician billing claims database.
abstract: OBJECTIVE
  (1) To determine the concordance between injury diagnoses (head injury (HI), probable HI, or orthopedic injury) for children visiting an emergency department for an injury using two
  
  
  METHODS
  an injury surveillance system (Canadian Hospitals Injury Research and Prevention Program, CHIRPP) and a physician billing claims database (Regie de l'assurance maladie de Quebec, RAMQ), and (2) to determine the sensitivity and specificity of diagnostic and procedure codes in billing claims for identifying HI and orthopedic injury among children.
  
  
  METHODS
  In this cross sectional cohort, data for 3049 children who sought care for an injury (2000-01) were obtained from both sources and linked using the child's personal health insurance number.
  
  
  METHODS
  The physician recorded diagnostic codes from CHIRPP were used to categorize the children into three groups (HI, probable HI, and orthopedic), while an algorithm, using ICD-9-CM diagnostic and procedures codes from the RAMQ, was used to classify children into the same three groups.
  
  
  RESULTS
  Concordance between the data sources was "substantial" (weighted Kappa 0.66; 95% CI 0.63 to 0.69). The sensitivity of diagnostic and procedure codes in the RAMQ database for identifying HI and for orthopedic injury were 0.61 (95% CI 0.57 to 0.64) and 0.97 (95% CI 0.96 to 0.98), respectively. The specificity for identifying HI and for orthopedic injury were 0.97 (95% CI 0.96 to 0.98) and 0.58 (95% CI 0.56 to 0.63), respectively.
  
  
  CONCLUSIONS
  Combining diagnostic and procedures codes in a physician billing claims database (the RAMQ database) may be a valid method of estimating injury occurrence among children.
authors.affiliation: Centre de recherche interdisciplinaire en réadaptation du Montréal métropolitain, Institut de réadaptation de Montréal; Montreal, Quebec, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Kostylova
authors.forename: B
authors.initials: B
authors.lastname: Swaine
authors.forename: D
authors.initials: D
authors.lastname: Feldman
mesh_terms: D000293:Adolescent; D002170:Canada / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004636:Emergency Service, Hospital / Q000458:organization & administration; D005249:Fees and Charges; D005260:Female; D006801:Humans; D007223:Infant; D007348:Insurance, Health; D008297:Male; D011159:Population Surveillance / Q000379:methods*; D012680:Sensitivity and Specificity; D014947:Wounds and Injuries / Q000175:diagnosis / Q000453:epidemiology*