... the definition of the BathAnkylosing Spondylitis Disease Activity Index (BASDAI) [21], the Bath Ankylosing Spondylitis Functional Index (BASFI), and the Bath Ankylosing Spondylitis Metrology ... and scientific understanding of the spondyloarthritides(SpA), which can be separated in predominantly axial and predominantly peripheral SpA. The clinical progress includes the development of ... manifes-ReviewDevelopments in the scientific and clinical understanding of the spondyloarthritidesJoachim SieperDepartment of Rheumatology, Campus Benjamin Franklin, Charité, Hindenburgdamm 30, 12200 Berlin, GermanyCorresponding...