CLASSIC (ASAS)
Research type
Research Study
Full title
CLassification of Axial SpondyloarthritiS Inception Cohort (CLASSIC)
IRAS ID
260885
Contact name
Helena Marzo-Ortega
Contact email
Sponsor organisation
Leeds Teaching Hospital NHS Trust
Duration of Study in the UK
5 years, 10 months, 1 days
Research summary
The ASAS group has developed classification criteria for axial spondyloarthritis (axSpA) that allow the inclusion of patients with an early form of disease that is not yet clearly visible on plain radiography.These criteria include both an imaging ‘arm’, that incorporates either radiographic sacroiliitis or magnetic resonance imaging (MRI) features of inflammation in the sacroiliac joints (SI-joints) plus one clinical feature of spondyloarthritis (SpA), and a clinical ‘arm’ that requires the presence of HLA-B27 plus 2 clinical features of SpA. The sensitivity and specificity of these criteria for axSpA were 83% and 84%, respectively.
Since their introduction, some have raised concerns regarding the validity of the ASAS classification criteria.Furthermore, there are concerns that the criteria may have been misused as a diagnostic checklist of SpA features to diagnose patients rather than following a process of diagnostic reasoning (clinical, lab, and imaging components) and differential diagnoses by an experienced clinician rheumatologist who then formulates a final diagnostic opinion before the classification criteria are applied.
It has been suggested that further education regarding appropriate ascertainment of SpA features and evaluation of imaging might help reduce mis-classification. In particular, there appears to be a lack of awareness and/or acceptance of the It is often difficult to find the correct diagnosis in the early phase of disease for patients with axial spondyloarthritis and it may take up to 8 years for people to be given a diagnosis. The ASAS classification criteria for axial spondyloarthritis are used to include patients with early disease in research projects. These criteria were developed 10 years ago and, since then, more knowledge has become available. Therefore, it is important to investigate whether these criteria are still appropriate today and if improvement is necessary.MRI and radiographs play an important role in the diagnosis and classification of axial spondyloarthritis. However, it can be difficult to recognize axial spondyloarthritis on MRIs or radiographs in an early phase of the disease. As time goes on, it often becomes more evident what the correct diagnosis is. Therefore, the participants would be invited for a review after 5 years for a re-evaluation of their diagnosis at this time point.
In the CLASSIC study, MRIs and radiographs will also be used to educate rheumatologists and radiologists in order to increase their knowledge about axial spondyloarthritis, thereby increasing the probability of a correct diagnosis. So, the main objective of this study is to gain a better insight in axial spondyloarthritis, enabling education of both radiologists and rheumatologists to better recognize this disease and thereby enabling early and better diagnosis of axial spondyloarthritis.
The CLASSIC study has been designed by the Assessment of SpondyloArthritis international Society (ASAS) group, an international group of experts in the field of axial spondyloarthritis, and will be carried out by rheumatologists in various hospitals in Europe and several centers outside Europe. A total of 1,000 participants from different countries will be included.
REC name
Yorkshire & The Humber - Sheffield Research Ethics Committee
REC reference
19/YH/0428
Date of REC Opinion
27 Mar 2020
REC opinion
Further Information Favourable Opinion