The Assessment of SpondyloArthritis International Society (ASAS) Consensus-Based Expert Definition of Difficult-to-Manage, including Treatment-Refractory, Axial Spondyloarthritis.

Poddubnyy D, Navarro-Compán V, Torgutalp M, Arends S, Aydin SZ, Battista S, van den Bosch F, Bundy C, Cauli A, Davies J, Dougados M, Duruöz T, El-Zorkany B, Fong W, van Gaalen F, Garcia-Salinas R, Garrido Cumbrera M, Géher P, Gensler L, Grazio S, Huang F, Kishimoto M, Landewé R, Leung YY, Machado PM, Marzo-Ortega H, Meghnathi B, Molto A, Nikiphorou E, Ramiro S, Rudwaleit M, Saad CGS, Sepriano A, Wei J, Baraliakos X, van der Heijde D, ASAS