Does ICD-9 coding indicate true incidence?
B. Taylor BACKGROUND: Recent reports in the scientific and lay press have suggested that bile duct injuries during laparoscopic cholecystectomy are common in Ontario. The reports were based on administrative data collected by hospital medical records departments and the Canadian Institute for Health Information (CIHI). The current study involved a direct inspection of hospital records to determine if the CIHI data accurately captured the rate of clinically significant bile duct complications. METHODS: For the period 1991 to 1995, records of bile duct injuries after laparoscopic cholecystectomy were independently evaluated to clarify the clinical significance of the complications. Of 21 Ontario hospitals for which data on complications had been reported in the media, 18 provided detailed information on all patients reported to have suffered bile duct complications classified by the hospital as “major”. In addition, each institution provided information on a random sample of one-sixth of
