1. Brigham and Women's Hospital; Boston Massachusetts
2. University of Massachusetts Medical School, Worcester and the Consortium of Rheumatology Researchers of North America (CORRONA); Southborough Massachusetts
3. Albany Medical College and Center for Rheumatology, Albany, New York and CORRONA; Southborough Massachusetts
4. University of Alabama at Birmingham
5. Mount Sinai School of Medicine; New York New York
6. University of Maryland School of Medicine; Baltimore
7. New York University School of Medicine and New York University Hospital for Joint Diseases, New York, New York, and CORRONA; Southborough Massachusetts