title: Quality of hospital discharge data for injury prevention.
abstract: OBJECTIVE
  To examine the use of unspecified codes for the circumstances of injury for New Zealand public hospital discharges at a district health board (DHB) level.
  
  
  METHODS
  Hospital injury discharges for the period 2000-3 were examined. The use of the International Classification of Diseases unspecified categories was examined for mechanism of injury, activity and place of occurrence.
  
  
  RESULTS
  For all DHBs, the combined age-adjusted and mechanism-adjusted usage of unspecified mechanism codes was 7% and ranged from 3% to 11%. Most (57%) of these cases were unspecified falls. The comparable usage for activity was 39% and ranged from 17% to 52%, and for place of occurrence the respective figures were 23% and 7-36%. Only 50% of hospital discharges were completely specified in terms of mechanism of injury, activity and place of occurrence; this varied from 36% to 74% between DHBs. For several DHBs a significant degree of inconsistency was found in performance across mechanism, activity and place of occurrence coding.
  
  
  CONCLUSIONS
  Those DHBs with a high proportion of cases coded as unspecified would serve the prevention efforts of their communities better by making efforts to determine the cause of this situation and implement measures to reduce the problem.
authors.affiliation: Injury Prevention Research Unit, Dunedin School of Medicine, Dunedin, New Zealand. john.langley@ipru.otago.ac.nz
authors.forename: John D
authors.initials: JD
authors.lastname: Langley
authors.forename: Gabrielle S
authors.initials: GS
authors.lastname: Davie
authors.forename: Jean C
authors.initials: JC
authors.lastname: Simpson
mesh_terms: D015998:Abbreviated Injury Scale; D000056:Accident Prevention / Q000379:methods / Q000706:statistics & numerical data*; D006753:Hospital Records / Q000592:standards*; D006801:Humans; D015601:Injury Severity Score; D038801:International Classification of Diseases; D008487:Medical History Taking / Q000592:standards; D009520:New Zealand; D010351:Patient Discharge; D011786:Quality Control; D014947:Wounds and Injuries / Q000209:etiology*