1. Division of Clinical Psychology, University of Liverpool, Liverpool
2. Clinical Research Support Centre, Education and Research Centre, Royal Group of Hospitals Trusts, Belfast
3. Department of Anaesthesia, Royal Liverpool University Hospital, Liverpool
4. Department of Anaesthesia, St George's Hospital Medical School, University of London, London
5. Outcomes Unit, Musgrave Park Hospital, Belfast
6. Division of Physiotherapy, University of Liverpool, Liverpool
7. Department of Orthopaedics, Musgrave Park Hospital, Belfast
8. Department of Orthopaedics, Royal Liverpool University Hospital
9. Division of Clinical Psychology, University of Liverpool, Liverpool, UK,