title: The Importance of Risk Adjustment in Reporting Total Joint Arthroplasty Outcomes.
abstract: BACKGROUND
  This study describes and tests a risk adjustment model developed for the California Joint Replacement Registry to report predictors of complication rates.
  
  
  METHODS
  Complication rates were analyzed for 9960 patients enrolled in the California Joint Replacement Registry at 22 medical centers. Multivariable logistic risk models were created to analyze risks of postoperative complications.
  
  
  RESULTS
  Age and American Society of Anesthesiologists class were the strongest predictors of complication rates (P < .0001). Congestive heart failure and peripheral vascular disease were also statistically significant predictors of complications. Three hospitals were found to have statistically significantly worse than expected complication rates, and one was found to have a better than expected complication rate after case mix risk adjustment.
  
  
  CONCLUSIONS
  Adequate risk adjustment is a key element in objective comparison of surgeons, hospitals, and devices using total joint arthroplasty registry data.
authors.affiliation: Department of Orthopaedic Surgery, University of California, Los Angeles, Santa Monica, California.
authors.forename: Nelson F
authors.initials: NF
authors.lastname: SooHoo
authors.affiliation: Department of Internal Medicine, University of California, Davis, School of Medicine, Sacramento, California.
authors.forename: Zhongmin
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Orthopaedic Surgery, University of California, San Francisco, San Francisco, California.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Chan
authors.affiliation: Pacific Business Group on Health, San Francisco, California.
authors.forename: Kate
authors.initials: K
authors.lastname: Chenok
authors.affiliation: Department of Orthopaedic Surgery, University of California, San Francisco, San Francisco, California.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Bozic
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects* / Q000706:statistics & numerical data; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects* / Q000706:statistics & numerical data; D002140:California; D016208:Databases, Factual; D005260:Female; D006333:Heart Failure / Q000150:complications; D006760:Hospitalization; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016491:Peripheral Vascular Diseases / Q000150:complications; D011183:Postoperative Complications; D012042:Registries; D012189:Retrospective Studies; D020379:Risk Adjustment
keywords: comorbidities; complications; registry; risk adjustment; total joint arthroplasty