Development of a new ultrasound scoring system to evaluate glandular inflammation in Sjögren’s syndrome: an OMERACT reliability exercise
Alojzija Hočevar, George A. W. Bruyn, Lene Terslev, Juan José de Agustín, Daryl MacCarter, Stavros Chrysidis, Paz Collado, Christian Dejaco, Viktoria Fana, Georgios Filippou, Stephanie Finzel, Frédérique Gandjbakhch, Petra Hánová, Daniel Hammenfors, Cristina Hernández‐Díaz, Annamaria Iagnocco, Mohamed Mortada, Nevsun İnanç, E. Naredo, Sarah Ohrndorf, Nejc Perko, Wolfgang Schmidt, Giorgio Tamborrini, Matija Tomšič, Isabelle Chary-Valckenaere, Alen Zabotti, Helen Keen, Carlos Pineda, Maria Antonietta D’Agostino, Sandrine Jousse‐Joulin
Abstract
OBJECTIVE: The aim of this exercise from the OMERACT Ultrasound subgroup on Sjögren's syndrome was to develop and assess the reliability of a consensus-based semiquantitative colour Doppler US scoring system for pathologic salivary gland vascularization in patients with primary Sjögren's syndrome (pSS). METHODS: Using the Delphi method, a colour Doppler semiquantitative scoring system for vascularization of bilateral parotid and submandibular glands was developed and tested in static images and on patients (9 pSS patients and 9 sonographers). Intra-reader and inter-reader reliability of grading the salivary glands were computed by weighted Cohen and Light's kappa analysis, respectively. RESULTS: The consensus-based semiquantitative score was: grade 0, no visible vascular signals; grade 1, focal, dispersed vascular signals; grade 2, diffuse vascular signals detected in <50% of the gland; grade 3, diffuse vascular signals in >50% of the gland. In static images, the intra- and inter-reader reliability showed excellent kappa values (95% CI) of 0.90 (0.87, 0.93) and 0.80 (0.74, 0.84), respectively, for all four salivary glands together. In patients, the intra- and inter-reader reliability for all four salivary glands together was kappa = 0.84 (0.73, 0.92) and 0.70 (0.64, 0.76), respectively. CONCLUSION: The consensus-based colour Doppler US scoring for the evaluation of salivary gland vascularization in pSS showed a good inter-reader reliability and excellent intra-reader reliability in static images and in patients. The clinical application of the developed scoring system should be tested in clinical settings.