title: Value of self-performed joint counts in rheumatoid arthritis patients near remission.
abstract: BACKGROUND
  To determine the validity and reliability of patients' self-performed joint counts compared to joint counts by professional assessors in rheumatoid arthritis (RA) patients in different disease activity states.
  
  
  METHODS
  In patients with established RA we determined the inter-rater reliability of joint counts performed by an independent evaluator and the patient using intraclass correlation (ICC), and agreement on activity in individual joints by kappa statistics. We also performed longitudinal analyses to assess consistency of assessments over time. Finally, we investigated the concordance of joint counts of different assessors in patients with different levels of disease activity.
  
  
  RESULTS
  The reliability of patient self-performed joint counts was high when compared to independent objective assessment (ICC; 95%confidence interval (CI)) for the assessment of swelling (0.32; 0.15 to 0.46) and tenderness (0.75; 0.66 to 0.81), with higher agreement for larger joints (kappa: 0.57 and 0.45, respectively) compared to smaller joints (metacarpo-phalangeal joint (MCPs): 0.31 and 0.45; and proximal interphalangeal joint (PIPs): 0.22 and 0.47, for swelling and tenderness, respectively).Patients in remission according to the Simplified Disease Activity Index (SDAI ≤ 3.3) showed better concordance of the joint counts (swollen joint count (SJC) ties 25/37, tender joint count (TJC) ties 26/37) compared to moderate/high disease activity states (SDAI > 11; MDA/HDA: SJC ties 9/72, TJC ties 21/72). Positive and negative predictive values regarding the presence of SDAI remission were reasonably good (0.86 and 0.95, respectively). A separate training session for patients did not improve the reliability of joint assessment. The results were consistent in the longitudinal analyses.
  
  
  CONCLUSIONS
  Self-performed joint counts are particularly useful for monitoring in patients having attained remission, as these patients seem able to detect state of remission.
authors.affiliation: Department of Internal Medicine III, Division of Rheumatology, Medical University of Vienna, Waehringerguertel 18-20, Vienna, 1090, Austria. helga.radner@meduniwien.ac.at
authors.forename: Helga
authors.initials: H
authors.lastname: Radner
authors.forename: Johannes
authors.initials: J
authors.lastname: Grisar
authors.forename: Josef S
authors.initials: JS
authors.lastname: Smolen
authors.forename: Tanja
authors.initials: T
authors.lastname: Stamm
authors.forename: Daniel
authors.initials: D
authors.lastname: Aletaha
mesh_terms: D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy; D002358:Cartilage, Articular / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006282:Health Personnel / Q000592:standards*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012074:Remission Induction; D016353:Self-Examination / Q000379:methods / Q000592:standards*; D016896:Treatment Outcome