1 Division of Rheumatology, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA. Electronic address: evolkmann@mednet.ucla.edu.
2 Division of Rheumatology, Inflammation, and Immunity, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
3 Department of Rheumatology, Oslo University Hospital-Rikshospitalet, Oslo, Norway; Department of Rheumatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
4 Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
5 Leeds NIHR Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK.
6 Université de Paris Cité, INSERM UMR 1152, Paris, France; Service de Rhumatologie, Hôpital Bichat-Claude Bernard, AP-HP, Paris, France.