title: Predicting patient satisfaction using the Oxford knee score: where do we draw the line?
abstract: OBJECTIVE
  The aim of this study was to identify threshold values in the pre- and post-operative Oxford knee score (OKS), and change in the score for differing levels of patient satisfaction with their total knee replacement (TKR).
  
  
  METHODS
  We prospectively collected pre-operative and 1-year post-operative OKS for 2392 patients undergoing a TKR. Patient satisfaction was categorically assessed, according to whether they were: very satisfied, satisfied, neutral, and unsatisfied. Receiver operating characteristic curve analysis was used to identify thresholds in the OKS score that identified each level of patient satisfaction.
  
  
  RESULTS
  The post-operative OKS was the most accurate predictor of the level of patient satisfaction (area under the curve = 0.86). Very satisfied patients had a threshold value in the post-operative OKS of ≥36, which decreased to ≥27 points for satisfied patients, and further still to ≤25 for unsatisfied patients.
  
  
  CONCLUSIONS
  The threshold values, we have identified for the different levels of satisfaction using the post-operative OKS, which is the most accurate predictor, can be used to predict level of patient satisfaction and give quantification of the OKS.
authors.affiliation: Department of Orthopaedics and Trauma, The Royal Infirmary of Edinburgh, Little France, Edinburgh, UK. nickclement@doctors.org.uk
authors.forename: Nicholas D
authors.initials: ND
authors.lastname: Clement
authors.forename: Deborah
authors.initials: D
authors.lastname: Macdonald
authors.forename: Richard
authors.initials: R
authors.lastname: Burnett
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D007592:Joint Diseases / Q000601:surgery*; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D012372:ROC Curve; D016896:Treatment Outcome; D055815:Young Adult