1. Centre for Trials Research, College of Biomedical and Life Sciences, Cardiff University, Cardiff, UK
2. Centre for the Development and Evaluation of Complex Interventions for Public Health Improvement (DECIPHer), College of Biomedical and Life Sciences, Cardiff University, Cardiff, UK
3. DECIPHer, School of Social Sciences, Cardiff University, Cardiff, UK
4. DECIPHer, School of Social and Community Medicine, University of Bristol, Bristol, UK
5. Public Health Wales, Swansea, UK
6. Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, London, UK
7. MRC/CSO Social and Public Health Sciences Unit, University of Glasgow, Glasgow, UK