10 Florance and Cope Professorial Department of Rheumatology, Royal North Shore Hospital and Institute of Bone and Joint Research, Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia.
11 Medicine Service, VA Medical Center, Department of Medicine at the School of Medicine, University of Alabama at Birmingham (UAB), Department of Epidemiology at the UAB School of Public Health, Birmingham, AL, USA.
12 Division of Immunology/Rheumatology, Stanford University School of Medicine, Palo Alto, CA, USA.
13 School of Epidemiology and Public Health, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada.