1. Department of Health Sciences, University of York, York, UK
2. School of Healthcare, Faculty of Medicine, University of Leeds, Leeds, UK
3. School of Health and Life Sciences/Institute for Applied Health Research, Glasgow Caledonian University, Glasgow, UK
4. National Institute for Health Research School for Primary Care Research, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
5. National Institute for Health Research Collaboration for Leadership in Applied Health Research and Care (CLAHRC) Greater Manchester, Centre for Primary Care, Institute of Population Health, University of Manchester, Manchester, UK
6. Medical Research Council/Chief Scientist Office Social and Public Health Sciences Unit, University of Glasgow, Glasgow, UK
7. Centre for Health Economics, University of York, York, UK