1. Department of Epidemiology and Biostatistics; University of California; San Francisco San Francisco, CA USA
2. Department of Epidemiology; Graduate School of Public Health; University of Pittsburgh; Pittsburgh PA USA
3. Amgen Inc; Thousand Oaks CA USA
4. Division of Epidemiology and Community Health and Department of Medicine; University of Minnesota; Minneapolis MN USA
5. Center for Chronic Diseases Outcomes Research; Minneapolis VA Health Care System; Minneapolis MN USA
6. Kaiser Permanente Center for Health Research; Northwest/Hawaii; Portland OR USA
7. California Pacific Medical Center Research Institute; San Francisco CA USA
8. Division of Health Policy and Management; University of Minnesota; Minneapolis MN USA
9. Università Campus Bio-Medico di Roma; Rome Italy
10. Istituto di ricovero e cura a carattere scientifico (IRCCS); Istituto Ortopedico Galeazzi; Milan Italy