1 National Institute of Arthritis, Musculoskeletal, and Skin Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892-1102, USA.
2 Section of Rheumatology, Allergy, and Immunology, Yale School of Medicine, New Haven, CT, USA.
3 Section of Rheumatology, Veteran Affairs Connecticut Healthcare System, West Haven, CT, USA.