1 Department of Family Medicine, University of North Carolina, Aycock Building, Manning Drive, CB #7595, UNC-Chapel Hill, Chapel Hill, NC, 27599-7595, USA. margaret_gourlay@med.unc.edu.
2 Department of Biostatistics, University of North Carolina, Chapel Hill, NC, USA.
3 NoviSci, LLC, Durham, NC, USA.
4 Department of Rheumatology, Park Nicollet Health Services, Minneapolis, MN, USA.
5 Division of Health Policy and Management, University of Minnesota, Minneapolis, MN, USA.
6 Research Institute, California Pacific Medical Center, San Francisco, CA, USA.
7 Bone and Mineral Unit, Oregon Health and Science University, Portland, OR, USA.
8 Garvan Institute of Medical Research, UNSW School of Public Health and Community Medicine, Kensington, NSW, Australia.
9 Centre for Health Technologies, University of Technology, Sydney, Australia.
10 Division of Rheumatology, Department of Medicine, Center for Musculoskeletal Health, UC Davis Health System, Sacramento, CA, USA.
11 Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, CA, USA.
12 Department of Medicine, University of California, San Diego, La Jolla, CA, USA.
13 School of Public Health, Oregon Health and Science University, Portland, OR, USA.
14 Department of Medicine, University of Minnesota, Minneapolis, MN, USA.
15 Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, USA.
16 Center for Chronic Disease Outcomes Research, VA Health Care System, Minneapolis, MN, USA.