1. Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Bristol, UK
2. Musculoskeletal Pharmaco- and Device Epidemiology, Centre for Statistics in Medicine, Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Sciences, University of Oxford, Oxford, UK
3. Department of Oncology and Metabolism, University of Sheffield, Sheffield, UK
4. Norwich Medical School, University of East Anglia, Norwich, UK