title: Improved coding of postoperative deep vein thrombosis and pulmonary embolism in administrative data (AHRQ Patient Safety Indicator 12) after introduction of new ICD-9-CM diagnosis codes.
abstract: BACKGROUND
  Symptomatic venous thromboembolism is a common postoperative complication. The Agency for Healthcare Research and Quality (AHRQ) has developed a Patient Safety Indicator 12 to assist hospitals, payers, and other stakeholders to identify patients who experienced this complication.
  
  
  OBJECTIVE
  To determine whether newly created and recently redefined ICD-9-CM codes improved the criterion validity of Patient Safety Indicator 12, based on new samples of records dated after October 2009.
  
  
  METHODS
  Two sources of data were used: (1) UHC retrospective case-control study of risk factors for acute symptomatic venous thromboembolism occurring within 90 days after total knee arthroplasty in teaching hospitals; (2) chart abstraction data by volunteer hospitals participating in the Validation Pilot Project of the AHRQ.
  
  
  RESULTS
  In the UHC sample, the positive predictive value (PPV) was 99% (125/126) and the negative predictive value was 99.4% (460/463). In the AHRQ sample, the overall PPV was 81% (126/156).
  
  
  CONCLUSIONS
  The PPV based on both samples shows substantial improvement compared with the previously reported PPVs of 43%-48%, suggesting that changes in ICD-9-CM code architecture and better coding guidance can improve the usefulness of coded data.
authors.affiliation: *Department of Medicine, Center for Healthcare Policy and Research, UC Davis School of Medicine, Sacramento †Center for Innovation and Improvement Science, University of California, San Diego ‡Center for Healthcare Policy and Research, University of California-Davis, Sacramento, CA §UHC, Chicago, IL.
authors.forename: Banafsheh
authors.initials: B
authors.lastname: Sadeghi
authors.forename: Richard H
authors.initials: RH
authors.lastname: White
authors.forename: Gregory
authors.initials: G
authors.lastname: Maynard
authors.forename: Patricia
authors.initials: P
authors.lastname: Zrelak
authors.forename: Amy
authors.initials: A
authors.lastname: Strater
authors.forename: Laurie
authors.initials: L
authors.lastname: Hensley
authors.forename: Julie
authors.initials: J
authors.lastname: Cerese
authors.forename: Patrick
authors.initials: P
authors.lastname: Romano
mesh_terms: D059019:Clinical Coding / Q000592:standards*; D006785:Hospitals, University; D006801:Humans; D038801:International Classification of Diseases / Q000592:standards*; D061214:Patient Safety; D011183:Postoperative Complications; D011655:Pulmonary Embolism / Q000175:diagnosis*; D019984:Quality Indicators, Health Care; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States; D016270:United States Agency for Healthcare Research and Quality; D054556:Venous Thromboembolism / Q000175:diagnosis*; D020246:Venous Thrombosis / Q000175:diagnosis*