1 Dept of Rheumatology, Oxford University Hospitals NHS FT, Windmill Road, Oxford, OX3 7HE and Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Windmill Road, Oxford, OX3 7LD.
2 Department of Rheumatology, Royal Berkshire NHS Foundation Trust, Craven Road, Reading RG1 5AN and Henley Business School, University of Reading, Whiteknights Road, Reading, RG6 6UD.
3 Faculty of Medicine Dentistry and Health, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX.
4 Northumbria Healthcare NHS Foundation Trust, 7, Northumbria House, Cobalt Business Park, 8 Silver Fox Way, Newcastle upon Tyne, NE27 0QJ.
5 Lancaster University, Bailrigg Lane, Lancaster, UK, and Rheumatology Department, Royal Lancaster Infirmary, Lancaster, UK.