1. Department of Medicine, Division of Rheumatology, University of California San Francisco , San Francisco, CA, USA
2. Institute for Health Policy Studies, University of California San Francisco , San Francisco, CA, USA
3. Department of Medicine, Division of Rheumatology, University of Pennsylvania , Philadelphia, PA, USA
4. National Institutes of Health, National Human Genome Research Institute , Bethesda, MD, USA
5. Centers for Disease Control and Prevention, Division of Population Health , Atlanta, GA, USA
6. Rheumatology Research Group, Institute of Inflammation and Ageing, University of Birmingham , Birmingham, UK