title: Responsiveness of the Liverpool Elbow Score in elbow arthroplasty.
abstract: BACKGROUND
  Responsiveness and floor and ceiling effect are important parameters for evaluating the sensitivity of an outcome instrument in detecting the changes in the clinical condition of patients after an intervention as well as evaluating the content validity of the instrument. The aim of this prospective observational study was to assess these parameters for the Liverpool Elbow Score (LES) in total elbow replacement (TER).
  
  
  METHODS
  The study included 121 cemented TER cases with linked elbow prosthesis (Discovery Elbow, Biomet Orthopaedics, Swindon, UK) for various conditions, including inflammatory arthritis, noninflammatory arthritis, trauma, and loosening. The proportion of patients with the lowest score (0 points; floor effect) and maximum score (10 points; ceiling effect) was checked preoperatively and 1 year postoperatively. Distribution-based methods (effect size [ES], standardized response mean [SRM], Guyatt responsiveness ratio [GRR]) and anchor-based methods (receiver operating characteristic [ROC] curve and Spearman correlation coefficient) were used to assess responsiveness. Patient satisfaction after TER was used as an external anchor.
  
  
  RESULTS
  Patients were a mean age of 63 years (range, 20-86 years). Large ES (1.64), SRM (1.25), and GRR (1.69) were found during the follow-up period. Area under the ROC curve was 0.71 (95% confidence interval, 0.56-0.87; P = .03). There was significant positive correlation (Spearman correlation coefficient, 0.35; P = .004) between changes in LES and satisfaction level. LES showed no floor and ceiling effect preoperatively and at 1 year postoperatively.
  
  
  CONCLUSIONS
  LES is a responsive measure and has no floor and ceiling effect.
  
  
  METHODS
  This encourages its use as an outcome instrument for TER. Basic Science Study, Development or Validation of Outcome Instruments.
authors: Countess of Chester Hospital, Chester, UK.
authors: Karthik
authors: K
authors: Vishwanathan
authors: Omid
authors: O
authors: Alizadehkhaiyat
authors: Graham J
authors: GJ
authors: Kemp
authors: Simon P
authors: SP
authors: Frostick
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D057929:Arthroplasty, Replacement, Elbow; D004551:Elbow Joint / Q000601:surgery*; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D007592:Joint Diseases / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D055815:Young Adult; D000092464:Elbow Injuries