title: Articular ultrasonography: interobserver reliability in rheumatoid arthritis.
abstract: BACKGROUND
  Ultrasonography (US) has a recent use in Rheumatology, and the reliability of the method in rheumatoid arthritis (RA) patients has yet to be clarified.
  
  
  OBJECTIVE
  To test, in a RA survey, the reproducibility of musculoskeletal US performed by rheumatologists with one-year training through re-analysis by a Rheumatologist experienced in the method.
  
  
  METHODS
  This cross-sectional study included consecutive RA patients from our tertiary center. US exam was performed in metacarpophalangeal joints, proximal interphalangeal joints, and wrists. Presence of synovitis, power Doppler (PD) signal, bone erosions, and cartilage changes comprised the US parameters evaluated. A kappa value in-between 0.20 and 0.40 was considered fair; in-between 0.41 and 0.60 was moderate; in-between 0.61 and 0.80 was good; and above 0.81 was excellent.
  
  
  RESULTS
  We analyzed 1,380 joints of 60 RA patients (78% females, 78% caucasoids). Mean age was 58 ± 11.56 years, mean disease duration was 9.98 ± 7.79 years, mean DAS28 was 3.82 ± 1.53, and mean HAQ was 0.91 ± 0.67. Kappa agreement for synovitis ranged from 0.30 to 0.70; for PD signal, from 0.53 to absolute agreement; for erosions, from 0.70 to 0.97; for cartilage changes, from 0.28 to 0.63.
  
  
  CONCLUSIONS
  Although good, moderate and excellent interobserver agreement were obtained for erosions and PD, concordance for synovitis and cartilage changes were less impressive in our patients with active RA. Further studies on standardization of scanning technique are necessary to improve musculoskeletal US reproducibility.
authors: Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brasil.
authors: Melissa Cláudia
authors: MC
authors: Bisi
authors: Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brasil.
authors: Aline Defaveri
authors: AD
authors: do Prado
authors: Faculdade de Medicina, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brasil.
authors: Cristina
authors: C
authors: Rabelo
authors: Faculdade de Medicina, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brasil.
authors: Flávia
authors: F
authors: Brollo
authors: Faculdade de Medicina, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brasil.
authors: Inês Guimarães
authors: IG
authors: da Silveira
authors: Pontifícia Universidade Católica de Campinas, Campinas, SP, Brasil.
authors: José Alexandre
authors: JA
authors: de Mendonça
authors: Faculdade de Medicina, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brasil.
authors: Henrique Luiz
authors: HL
authors: Staub
mesh_terms: D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D014463:Ultrasonography