1. John A. Burns School of Medicine, Honolulu, HI, USA,
2. SAS Institute, Cary, NC, USA,
3. Department of Medicine, Division of Geriatric Medicine, Center for Aging and Health, University of North Carolina, Chapel Hill, NC, USA,
4. Department of Medicine, Division of Rheumatology, Allergy, and Immunology, Thurston Arthritis Research Center, University of North Carolina, Chapel Hill, NC, USA,
5. Department of Orthopaedics, University of North Carolina, Chapel Hill, NC, USA, and
6. Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA