1. International Centre for Evidence in Disability, London School of Hygiene & Tropical Medicine, Keppel Street, LondonWC1E7HT, UK
2. Indian Institute of Public Health, Plot No #1, A.N.V. Arcade, Amar Co-op Society, Kavuri Hills, Madhapur, Hyderabad, 500033, India
3. Nuffield Department of Orthopaedics Rheumatology and Musculoskeletal Science, University of Oxford, UK