EULAR/ACR classification criteria for adult and juvenile idiopathic inflammatory myopathies and their major subgroups: a methodology report. Issue 2 (14th November 2017)

• Record Type: Journal Article
• Authors: Bottai, Matteo; Tjärnlund, Anna; Santoni, Giola; Werth, Victoria P; Pilkington, Clarissa; de Visser, Marianne; Alfredsson, Lars; Amato, Anthony A; Barohn, Richard J; Liang, Matthew H; Singh, Jasvinder A; Aggarwal, Rohit; Arnardottir, Snjolaug; Chinoy, Hector; Cooper, Robert G; Danko, Katalin; Dimachkie, Mazen M; Feldman, Brian M; García-De La Torre, Ignacio; Gordon, Patrick; Hayashi, Taichi; Katz, James D; Kohsaka, Hitoshi; Lachenbruch, Peter A; Lang, Bianca A; Li, Yuhui; Oddis, Chester V; Olesinka, Marzena; Reed, Ann M; Rutkowska-Sak, Lidia; Sanner, Helga; Selva-O'Callaghan, Albert; Wook Song, Yeong; Vencovsky, Jiri; Ytterberg, Steven R; Miller, Frederick W; Rider, Lisa G; Lundberg, Ingrid E;
• Other Names: Amoruso Maria author non-byline.; Andersson Helena author non-byline.; Bayat Nastaran author non-byline.; Bhansing Kavish J author non-byline.; Bucher Sara author non-byline.; Champbell Richard author non-byline.; Charles-schoeman Christina author non-byline.; Chaudhry Vinay author non-byline.; Christopher-stine Lisa author non-byline.; Chung Lorinda author non-byline.; Cronin Mary author non-byline.; Curry Theresa author non-byline.; Dahlbom Kathe author non-byline.; Distler Oliver author non-byline.; Efthimiou Petros author non-byline.; Van engelen Baziel Gm author non-byline.; Faiq Abdullah author non-byline.; Farhadi Payam Noroozi author non-byline.; Fiorentino David author non-byline.; Hengstman Gerald author non-byline.; Hoogendijk Jessica author non-byline.; Huber Adam author non-byline.; Kataoka Hiroshi author non-byline.; Katsumata Yasuhiro author non-byline.; Kim Susan author non-byline.; Kong-rosario Michelle author non-byline.; Kontzias Apostolos author non-byline.; Krol Petra author non-byline.; Kurita Takashi author non-byline.; Li Zhan-guo author non-byline.; Lindvall Björn author non-byline.; Linklater Helen author non-byline.; Maillard Sue author non-byline.; Mamyrova Gulnara author non-byline.; Mantegazza Renato author non-byline.; Marder Galina S author non-byline.; Nagahashi marie Suely Kazue author non-byline.; Mathiesen Pernille author non-byline.; Mavragani Clio P author non-byline.; Mchugh Neil J author non-byline.; Michaels Mimi author non-byline.; Mohammed Reem author non-byline.; Morgan Gabrielle author non-byline.; Moser David W author non-byline.; Moutsopoulos Haralampos M author non-byline.;
• Is Part Of: RMD open. Volume 3:Issue 2(2017)
• Publication Date: 2017-11-14
• Subjects: dermatomyositis -- polymyositis -- autoimmune diseases; Musculoskeletal system -- Diseases -- Periodicals; Rheumatism -- Periodicals; 616.7005
• DOI: 10.1136/rmdopen-2017-000507
• Languages: English
• ISSNs: 2056-5933

Abstract

Abstract : Objective: To describe the methodology used to develop new classification criteria for adult and juvenile idiopathic inflammatory myopathies (IIMs) and their major subgroups. Methods: An international, multidisciplinary group of myositis experts produced a set of 93 potentially relevant variables to be tested for inclusion in the criteria. Rheumatology, dermatology, neurology and paediatric clinics worldwide collected data on 976 IIM cases (74% adults, 26% children) and 624 non-IIM comparator cases with mimicking conditions (82% adults, 18% children). The participating clinicians classified each case as IIM or non-IIM. Generally, the classification of any given patient was based on few variables, leaving remaining variables unmeasured. We investigated the strength of the association between all variables and between these and the disease status as determined by the physician. We considered three approaches: (1) a probability-score approach, (2) a sum-of-items approach criteria and (3) a classification-tree approach. Results: The approaches yielded several candidate models that were scrutinised with respect to statistical performance and clinical relevance. The probability-score approach showed superior statistical performance and clinical practicability and was therefore preferred over the others. We developed a classification tree for subclassification of patients with IIM. A calculator for electronic devices, such as computers and smartphones, facilitates the use of the European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) classification criteria. Conclusions: The new EULAR/ACR classification criteria provide a patient's probability of having IIM for use in clinical and research settings. The probability is based on a score obtained by summing the weights associated with a set of criteria items.