1 Pediatrics, Division of Rheumatology, Seattle Children's Hospital, Seattle, Washington, USA [email protected].
2 University of Washington School of Medicine, Seattle, Washington, USA.
3 The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
4 Harvard Medical School, Boston, Massachusetts, USA.
5 University of Colorado School of Medicine, Aurora, Colorado, USA.
6 Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.
7 Indiana University School of Medicine, Indianapolis, Indiana, USA.
8 The Hospital for Sick Children, Toronto, Ontario, Canada.
9 Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
10 Intramural Research Program, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland, USA.
11 Division of Pediatric Rheumatology, Children\'s Hospital at Montefiore, Bronx, New York, USA.
12 Division of Pediatric Rheumatology, Yeshiva University Albert Einstein College of Medicine, Bronx, New York, USA.
13 Duke University School of Medicine, Durham, North Carolina, USA.
14 University of California San Francisco School of Medicine, San Francisco, California, USA.
15 Faculty of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada.
16 BC Children's Hospital, Vancouver, British Columbia, Canada.
17 National Institute of Environmental Health Sciences, Durham, North Carolina, USA.