1. Rheumatology Research Unit, Department of Rheumatology, Cambridge University Hospitals, Cambridge, UK
2. Department of Pain Medicine, Walton Centre, Liverpool, UK
3. Department of Anaesthetics, Derriford Hospital, Plymouth, UK
4. Department of ICT, University of Southampton, Southampton, UK
5. Epidemiology Group, Institute for Applied Health Sciences, University of Aberdeen, Aberdeen, UK
6. Department of Primary Care Research, University of Cambridge, Cambridge, UK
7. Department of Clinical, Educational & Health Psychology, University College London, London, UK
8. Centre for Health and Clinical Research, University of the West of England, Bristol, UK