2276 A Validation of Hysterectomy Procedural Codes in the Canadian Institutes for Health Information Discharge Abstract Database

Abstract

Study Objective The Canadian Institute of Health Information (CIHI) Discharge Abstract Database (DAD) is the main source of routinely-collected for gynecologic surgery in Canada and increasingly used for research. As these data were originally collected for healthcare administrative purposes, they are prone to error and should be validated for clinical research. The objective was to validate hysterectomy codes from the CIHI-DAD at a single institution. Design Retrospective consecutive sample Setting The Ottawa Hospital (TOH), Ontario, Canada Patients or Participants We obtained a consecutive sample of all gynecologic procedures performed at TOH between April 2016 and March 2017 using the CIHI-DAD at the Ottawa Hospital. Patient data including diagnosis, procedure type, and surgical approach, were reabstracted from charts. Reabstracted chart data were compared to CIHI-DAD Canadian Classification of Health Interventions (CCI) codes using sensitivity, specificity, positive and negative predictive value (PPV, NPV) and kappa coefficient with associated 95% confidence intervals (CI). Interventions N/A Measurements and Main Results Of 1079 gynecologic procedures, 649 hysterectomies were performed, including 23.3% vaginally, 17.1% laparoscopically, and 14.9% abdominally. The median patient age was 46 years (Range:41-54). The sensitivity, specificity, PPV, NPV, and kappa, with associated 95% confidence intervals, for all hysterectomies was 94.8% (92.8-96.4%), 88.4% (85.0-91.3%), 92.5% (90.2-94.4%), 91.8% (88.7-94.3%) and 0.84 (0.80-0.87), respectively. For vaginal hysterectomy, sensitivity=88.8% (84.3-92.5%), specificity=99.2% (98.3-99.7%), PPV=97.0% (93.8-98.9%), NPV=96.7% (95.3-97.8%), and kappa=0.91(0.87-0.94). For laparoscopic hysterectomy, sensitivity=91.3% (86.3-95.0%), specificity=92.8% (91.0-94.4), PPV=72.4% (66.2-78.1%), NPV=98.1% (97.0-98.9%), and kappa=0.79 (0.71-0.81). For abdominal hysterectomy, sensitivity=96.9% (93.9-99.0%), specificity=94.9% (93.2-96.2%), PPV=76.8% (70.4-82.5%), NPV=99.4% (98.7-99.8%), and kappa=0.83 (0.78-0.87). Conclusion Our study suggests a high level of validity for hysterectomy CCI codes in the CIHI-DAD for clinical research purposes.