TY - JOUR T1 - Ultrasound as an Outcome Measure in Gout. A Validation Process by the OMERACT Ultrasound Working Group JF - The Journal of Rheumatology JO - J Rheumatol SP - 2177 LP - 2181 DO - 10.3899/jrheum.141294 VL - 42 IS - 11 AU - Lene Terslev AU - Marwin Gutierrez AU - Wolfgang A. Schmidt AU - Helen I. Keen AU - Emilio Filippucci AU - David Kane AU - Ralf Thiele AU - Gurjit Kaeley AU - Peter Balint AU - Peter Mandl AU - Andrea Delle Sedie AU - Hilde Berner Hammer AU - Robin Christensen AU - Ingrid Möller AU - Carlos Pineda AU - Eugene Kissin AU - George A. Bruyn AU - Annamaria Iagnocco AU - Esperanza Naredo AU - Maria Antonietta D’Agostino Y1 - 2015/11/01 UR - http://www.jrheum.org/content/42/11/2177.abstract N2 - Objective. To summarize the work performed by the Outcome Measures in Rheumatology (OMERACT) Ultrasound (US) Working Group on the validation of US as a potential outcome measure in gout.Methods. Based on the lack of definitions, highlighted in a recent literature review on US as an outcome tool in gout, a series of iterative exercises were carried out to obtain consensus-based definitions on US elementary components in gout using a Delphi exercise and subsequently testing these definitions in static images and in patients with proven gout. Cohen’s κ was used to test agreement, and values of 0–0.20 were considered poor, 0.20–0.40 fair, 0.40–0.60 moderate, 0.60–0.80 good, and 0.80–1 excellent.Results. With an agreement of > 80%, consensus-based definitions were obtained for the 4 elementary lesions highlighted in the literature review: tophi, aggregates, erosions, and double contour (DC). In static images interobserver reliability ranged from moderate to almost perfect, and similar results were found for the intrareader reliability. In patients the intraobserver agreement was good for all lesions except DC (moderate). The interobserver agreement was poor for aggregates and DC but moderate for the other components.Conclusion. These first steps in evaluating the validity of US as an outcome measure for gout show that the reliability of the definitions ranged from moderate to excellent in static images and somewhat lower in patients, indicating that a standardized scanning technique may be needed, before testing the responsiveness of those definitions in a composite US score. ER -