1Division of Endocrinology and Diabetes, University Campus Bio-Medico di Roma, Rome, Italy
2Department of Internal Medicine, Division of Bone and Mineral Diseases, Musculoskeletal Research Center, Washington University School of Medicine, St. Louis, MO, USA
3Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Open University, Rome, Italy
4Metabolic Bone Centre, Northern General Hospital, Sheffield, UK
5Department Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, USA
6Departments of Medicine and Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, USA
7Center for Aging and Population Health, Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
8Institute for Aging Research, Hebrew SeniorLife, Boston, MA, USA
9Department of Medicine, Harvard Medical School, Boston, MA, USA
10Division of Gerontology, Beth Israel Deaconess Medical Center, Boston, MA, USA