Salivary Gland Ultrasonography in Sjögren's Syndrome: A European Multicenter Reliability Exercise for the HarmonicSS Project
Alen Zabotti, Sara Zandonella Callegher, Annarita Tullio, Arso M. Vukićević, Alojzija Hočevar, Vera Milić, Giacomo Cafaro, Marina Carotti, Konstantina Delli, Orazio De Lucia, Diana Ernst, Francesco Ferro, Angelica Gattamelata, Giuseppe Germanò, Ivan Giovannini, Daniel Hammenfors, Malin V. Jonsson, Sandrine Jousse‐Joulin, Pierluigi Macchioni, Simone Parisi, Carlo Perricone, Martin Stradner, Nenad Filipović, Athanasios G. Tzioufas, Francesca Valent, Salvatore De Vita
Abstract
Objectives: Salivary gland ultrasonography (SGUS) is increasingly applied for the management of primary Sjögren's syndrome (pSS). This study aims to: (i) compare the reliability between two SGUS scores; (ii) test the reliability among sonographers with different levels of experience. Methods: In the reliability exercise, two four-grade semi-quantitative SGUS scoring systems, namely De Vita et al. and OMERACT, were tested. The sonographers involved in work-package 7 of the HarmonicSS project from nine countries in Europe were invited to participate. Different levels of sonographers were identified on the basis of their SGUS experience and of the knowledge of the tested scores. A dedicated atlas was used as support for SGUS scoring. Results: Twenty sonographers participated in the two rounds of the reliability exercise. The intra-rater reliability for both scores was almost perfect, with a Light's kappa of 0.86 for the De Vita et al. score and 0.87 for the OMERACT score. The inter-rater reliability for the De Vita et al. and the OMERACT score was substantial with Light's Kappa of 0.75 and 0.77, respectively. Furthermore, no significant difference was noticed among sonographers with different levels of experience. Conclusion: The two tested SGUS scores are reliable for the evaluation of major salivary glands in pSS, and even less-expert sonographers could be reliable if adequately instructed.