1Osteoporosis and Bone Metabolism Unit, Department of Endocrinology, Singapore General Hospital, Singapore, Singapore
2Ministry of Health, Singapore, Singapore
3School of Public Health, National University of Singapore, Singapore, Singapore
4Center for Investigation in Bone and Articular Cartilage, University of Liege, Liege, Belgium
5Department of Health Services Research, CAPHRI Care and Public Health Research Institute, Maastricht University, Maastricht, The Netherlands