1. University of Sydney; Sydney New South Wales Australia
2. The George Institute for Global Health and Institute of Bone and Joint Research, The Kolling Institute, University of Sydney; Sydney New South Wales Australia
3. Murcia Twin Registry, University of Murcia and IMIB-Arrixaca; Murcia Spain
4. The George Institute for Global Health, University of Sydney; Sydney New South Wales Australia
5. University of Sydney, Sydney, New South Wales, Australia & Universidade Federal do Rio Grande do Sul; Porto Alegre Brazil