1San Francisco Coordinating Center, California Pacific Medical Center Research Institute, San Francisco, CA, United States of America
2Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, United States of America
3Division of Endocrinology, Metabolism and Nutrition, Department of Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, United States of America
4Botnar Research Centre, Nuffield Department of Orthopaedics, Rheumatology & Musculoskeletal Sciences, University of Oxford, Oxford, UK
5Mellanby Centre for Bone Research, University of Sheffield, Sheffield, UK