RT Journal Article SR Electronic T1 An International Delphi Survey for the Definition of New Classification Criteria for Familial Mediterranean Fever, Mevalonate Kinase Deficiency, TNF Receptor–associated Periodic Fever Syndromes, and Cryopyrin-associated Periodic Syndrome JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP jrheum.180056 DO 10.3899/jrheum.180056 A1 Silvia Federici A1 Federica Vanoni A1 Eldad Ben-Chetrit A1 Luca Cantarini A1 Joost Frenkel A1 Raphaela Goldbach-Mansky A1 Ahmet Gul A1 Hal Hoffman A1 Isabelle Koné-Paut A1 Jasmin Kuemmerle-Deschner A1 Helen J. Lachmann A1 Alberto Martini A1 Laura Obici A1 Seza Ozen A1 Anna Simon A1 Michael Hofer A1 Nicolino Ruperto A1 Marco Gattorno YR 2018 UL http://www.jrheum.org/content/early/2018/10/25/jrheum.180056.abstract AB Objective Provisional evidence-based classification criteria for hereditary periodic fever (HPF) have been recently developed. However, no consensus on how to combine clinical criteria, laboratory tests, and results of molecular analysis has been reached. The objective of this study is to understand which variables physicians consider important for the classification of patients with HPF. Methods Two Delphi surveys were sent to health professionals in the field of autoinflammation. In the first open survey, 124 researchers could list all the variables they consider useful for the diagnosis of each monogenic periodic fever. The variables could be of any type and each researcher could complete the survey for 1 or more diseases. In the second survey, 162 researchers were asked to select, from a list of items coming from the first survey, the 10 top variables and to rank them by assigning a score from 10 to 1. Results The response rates to the Delphi surveys were 85% for the first session and 87% for the second. The variables selected for each disease (corresponding to the third quartile, considering the total score obtained by the variables after the second Delphi survey) were 21 for mevalonate kinase deficiency, 22 for cryopyrinopathies, 18 for familial Mediterranean fever, and 20 for tumor necrosis factor receptor–associated periodic fever syndrome. A positive genetic test reached the top rank in all the HPF. Conclusion Our process led to the identification of those features considered the most important as candidate variables to be included in a new set of evidence-based classification criteria for HPF.