1 Division of Rheumatology, Allergy, and Immunology, Department of Medicine, Massachusetts General Hospital, Boston, Mass; Clinical Epidemiology Program, The Mongan Institute, Massachusetts General Hospital, Boston, Mass; Harvard Medical School, Boston, Mass. Electronic address: lbrobinson@mgh.harvard.edu.
2 Harvard Medical School, Boston, Mass; Department of Emergency Medicine, Brigham and Women's Hospital, Boston, Mass.
3 Harvard Medical School, Boston, Mass; Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, Mass.
4 Harvard Medical School, Boston, Mass; Massachusetts General Brigham, Sommerville, Mass.
5 Clinical Epidemiology Program, The Mongan Institute, Massachusetts General Hospital, Boston, Mass; Harvard Medical School, Boston, Mass.
6 Division of Rheumatology, Allergy, and Immunology, Department of Medicine, Massachusetts General Hospital, Boston, Mass; Clinical Epidemiology Program, The Mongan Institute, Massachusetts General Hospital, Boston, Mass; Harvard Medical School, Boston, Mass; Department of Emergency Medicine, Massachusetts General Hospital, Boston, Mass.
7 Harvard Medical School, Boston, Mass; Division of Allergy and Clinical Immunology, Department of Medicine, Brigham and Women's Hospital, Boston, Mass.
8 Division of Rheumatology, Allergy, and Immunology, Department of Medicine, Massachusetts General Hospital, Boston, Mass; Clinical Epidemiology Program, The Mongan Institute, Massachusetts General Hospital, Boston, Mass; Harvard Medical School, Boston, Mass.