1. Division of Health Research, Lancaster University, Lancaster, UK
2. Department of Anthropology, Durham University, Durham, UK
3. Population Health Sciences Institute, Newcastle University, Newcastle-upon-Tyne, UK
4. Department of Public Health, Policy and Systems, The University of Liverpool, Liverpool, UK
5. Department of Public Health, Environments and Society, London School of Hygiene & Tropical Medicine, London, UK
6. Department of Health Services Research and Policy, London School of Hygiene & Tropical Medicine, London, UK