1 Department of Rheumatology, St James's Hospital, Dublin, Ireland.
2 Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
3 Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, and NIHR Leeds Biomedical Research Unit, Leeds Teaching Hospitals NHS Trust, UK; s.l.mackie@leeds.ac.uk.
4 Centre for Inflammation and Tissue Repair, UCL Respiratory, Division of Medicine, University College London, and Department of Rheumatology, University College London Hospital (UCLH) NHS Trust, London, UK.
5 Medical College of Wisconsin, Milwaukee, Wisconsin, USA.
6 University of Queensland Faculty of Medicine, Brisbane, Australia.
7 Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.