title: Retrospective Derivation and Validation of an Automated Electronic Search Algorithm to Identify Post Operative Cardiovascular and Thromboembolic Complications.
abstract: BACKGROUND
  With increasing numbers of hospitals adopting electronic medical records, electronic search algorithms for identifying postoperative complications can be invaluable tools to expedite data abstraction and clinical research to improve patient outcomes.
  
  
  OBJECTIVE
  To derive and validate an electronic search algorithm to identify postoperative thromboembolic and cardiovascular complications such as deep venous thrombosis, pulmonary embolism, or myocardial infarction within 30 days of total hip or knee arthroplasty.
  
  
  METHODS
  A total of 34 517 patients undergoing total hip or knee arthroplasty between January 1, 1996 and December 31, 2013 were identified. Using a derivation cohort of 418 patients, several iterations of a free-text electronic search were developed and refined for each complication. Subsequently, the automated search algorithm was validated on an independent cohort of 2 857 patients, and the sensitivity and specificities were compared to the results of manual chart review.
  
  
  RESULTS
  In the final derivation subset, the automated search algorithm achieved a sensitivity of 91% and specificity of 85% for deep vein thrombosis, a sensitivity of 96% and specificity of 100% for pulmonary embolism, and a sensitivity of 100% and specificity of 95% for myocardial infarction. When applied to the validation cohort, the search algorithm achieved a sensitivity of 97% and specificity of 99% for deep vein thrombosis, a sensitivity of 97% and specificity of 100% for pulmonary embolism, and a sensitivity of 100% and specificity of 99% for myocardial infarction.
  
  
  CONCLUSIONS
  The derivation and validation of an electronic search strategy can accelerate the data abstraction process for research, quality improvement, and enhancement of patient care, while maintaining superb reliability compared to manual review.
authors.affiliation: Mayo Clinic, College of Medicine , Rochester, MN, United States.
authors.forename: M
authors.initials: M
authors.lastname: Tien
authors.affiliation: Mayo Clinic , Department of Anesthesiology, Rochester, MN, United States.
authors.forename: R
authors.initials: R
authors.lastname: Kashyap
authors.affiliation: Mayo Clinic , Division of Pulmonary and Critical Care Medicine, Rochester, MN, United States.
authors.forename: G A
authors.initials: GA
authors.lastname: Wilson
authors.affiliation: Mayo Clinic , Department of Anesthesiology, Rochester, MN, United States.
authors.forename: V
authors.initials: V
authors.lastname: Hernandez-Torres
authors.affiliation: Mayo Clinic , Department of Anesthesiology, Rochester, MN, United States.
authors.forename: A K
authors.initials: AK
authors.lastname: Jacob
authors.affiliation: Mayo Clinic, Health Sciences Research - Biomedical Statistics and Informatics , Rochester, MN, United States.
authors.forename: D R
authors.initials: DR
authors.lastname: Schroeder
authors.affiliation: Mayo Clinic , Department of Anesthesiology, Rochester, MN, United States.
authors.forename: C B
authors.initials: CB
authors.lastname: Mantilla
mesh_terms: D000465:Algorithms; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects; D001331:Automation; D057225:Data Mining / Q000379:methods*; D057286:Electronic Health Records; D006801:Humans; D008490:Medical Informatics; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000209:etiology; D011183:Postoperative Complications / Q000175:diagnosis* / Q000209:etiology; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000209:etiology; D012189:Retrospective Studies; D020246:Venous Thrombosis / Q000175:diagnosis* / Q000209:etiology
keywords: Clinical research informatics; myocardial infarction; search algorithm; venous thromboembolism