Article Text

other Versions

Download PDFPDF
The Development of Assessment of SpondyloArthritis international Society (ASAS) Classification Criteria for Axial Spondyloarthritis (Part II): Validation and Final Selection
  1. M Rudwaleit (martin.rudwaleit{at}
  1. Rheumatology, Med. Klinik I, Charité - Campus Benjamin Franklin, Berlin, Germany
    1. D van der Heijde (d.vanderheijde{at}
    1. Leiden University Medical Center, Leiden, Netherlands
      1. R Landewé (r.landewe{at}
      1. Maastricht University Medical Center, Maastricht, Netherlands
        1. J Listing (listing{at}
        1. Epidemiology Unit, German Rheumatism Research Centre, Berlin, Germany
          1. N Akkoc (akkoc{at}
          1. Dokuz Eylul University Hospital, Izmir, Turkey
            1. J Brandt (brandt.rheumatologie{at}
            1. Rheumatology Private Practice, Berlin, Germany
              1. J Braun (j.braun{at}
              1. Rheumazentrum Ruhrgebiet, Herne, and Ruhr-University, Bochum, Germany
                1. C T Chou (ctchou1007{at}
                1. Veterans General Hospital, Taipei, Taiwan
                  1. E Collantes-Estevez (eduardo.collantes.sspa{at}
                  1. University of Córdoba, Cordoba, Spain
                    1. M Dougados (m.doug{at}
                    1. Hospital Cochin, Paris, France
                      1. F Huang (fhuang1964{at}
                      1. Chinese PLA General Hospital, Beijing, China
                        1. J Gu (gujieruo{at}
                        1. Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
                          1. M A Khan (mkhan{at}
                          1. Case Western Reserve University, MetroHealth Medical Center, Cleveland, OH, United States
                            1. Y Kirazli (yesim.kirazli{at}
                            1. 12 University of Ege, Izmir, Turkey
                              1. W P Maksymowych (walter.maksymowych{at}
                              1. University of Alberta, Edmonton, Canada
                                1. H Mielants (herman.mielants{at}
                                1. University Hospital, Ghent, Belgium
                                  1. I J Sørensen (inge.juul.soerensen{at}
                                  1. University Hospital, Copenhagen, Denmark
                                    1. S Ozgocmen (sozgocmen{at}
                                    1. First University Hospital, Elazig, Turkey
                                      1. E Roussou (thaliaroussou{at}
                                      1. King George Hospital, London, United Kingdom
                                        1. R Valle-Onate (ravalleo1{at}
                                        1. University Militar Hospital, Bogotá, Colombia
                                          1. U Weber ({at}
                                          1. Balgrist University Hospital, Zurich, Switzerland
                                            1. J Wei (wei3228{at}
                                            1. Chung Shan Medical University, Taichung, Taiwan
                                              1. J Sieper (joachim.sieper{at}
                                              1. Rheumatology, Med. Klinik I, Charité, Berlin and German Rheumatology Research Center, Berlin, Germany


                                                Objective: To validate and refine two sets of candidate criteria for classification/ diagnosis of axial spondyloarthritis (SpA).

                                                Methods: All ASAS members were invited to include consecutively new patients with chronic (≥3 months) back pain of unknown origin that began before 45 years of age. The candidate criteria were first tested in the entire cohort of 649 patients from 25 centres, and then refined in a random selection of 40% of cases and thereafter validated in the remaining 60%.

                                                Results: Upon diagnostic work up, axial SpA was diagnosed in 60.2% of the cohort. Of these, 70% did not fulfil modified New York criteria, and, therefore, were classified as having "non-radiographic" axial SpA. Refinement of the candidate criteria resulted in new ASAS classification criteria which are defined as: presence of sacroiliitis by radiography or by MRI plus at least 1 SpA feature ("imaging arm"), or presence of HLA-B27 plus at least 2 SpA features ("clinical arm"). Sensitivity and specificity of the entire set of the new criteria were 82.9% and 84.4%, and for the imaging arm alone 66.2% and 97.3%, respectively. The specificity of the new criteria was much better than that of the ESSG criteria modified for MRI (sensitivity 85.1%, specificity 65.1%) and slightly better than that of the modified Amor criteria (sensitivity 82.9, specificity 77.5%).

                                                Conclusion: The new ASAS classification criteria for axial SpA can reliably classify patients for clinical studies, and may help rheumatologists in clinical practice in diagnosing axial SpA in those with chronic back pain.

                                                Statistics from

                                                Request Permissions

                                                If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

                                                Linked Articles