title: The importance of sonographer experience and machine quality with regards to the role of musculoskeletal ultrasound in routine care of rheumatoid arthritis patients.
abstract: OBJECTIVE
  Regarding recent progress, musculoskeletal ultrasound (US) will probably soon be integrated in standard care of patient with rheumatoid arthritis (RA). However, in daily care, quality of US machines and level of experience of sonographers are varied. We conducted a study to assess reproducibility and feasibility of an US scoring for RA, including US devices of different quality and rheumatologist with various levels of expertise in US as it would be in daily care.
  
  
  METHODS
  The Swiss Sonography in Arthritis and Rheumatism (SONAR) group has developed a semi-quantitative score using OMERACT criteria for synovitis and erosion in RA. The score was taught to 108 rheumatologists trained in US. One year after the last workshop, 19 rheumatologists participated in the study. Scans were performed on 6 US machines ranging from low to high quality, each with a different patient. Weighted kappa was calculated for each pair of readers.
  
  
  RESULTS
  Overall, the agreement was fair to moderate. Quality of device, experience of the sonographers and practice of the score before the study improved substantially the agreement. Agreement assessed on higher quality machine, among sonographers with good experience in US increased to substantial (median kappa for B-mode and Doppler: 0.64 and 0.41 for erosion).
  
  
  CONCLUSIONS
  This study demonstrated feasibility and reproducibility of the Swiss US SONAR score for RA. Our results confirmed importance of the quality of US machine and the training of sonographers for the implementation of US scoring in the routine daily care of RA.
authors.affiliation: Rheumatology HUG, Geneva, Switzerland.
authors.forename: Laure
authors.initials: L
authors.lastname: Brulhart
authors.affiliation: OsteoRheuma Bern, Bern Switzerland.
authors.forename: Hans-Rudolf
authors.initials: HR
authors.lastname: Ziswiler
authors.affiliation: Rheumatology and Ultrasound Department, Bethesda Hospital Basel, Switzerland.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Tamborrini
authors.affiliation: RH/DAL, CHUV, Lausanne, Switzerland.
authors.forename: Pascal
authors.initials: P
authors.lastname: Zufferey
mesh_terms: D000368:Aged; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging*; D002983:Clinical Competence / Q000592:standards*; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007596:Joints / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011237:Predictive Value of Tests; D019984:Quality Indicators, Health Care / Q000592:standards*; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D059039:Standard of Care / Q000592:standards; D013557:Switzerland; D018608:Ultrasonography, Doppler / Q000295:instrumentation / Q000592:standards*