1. School of Nursing and Midwifery, Queen’s University Belfast, Belfast, UK
2. Department of Public Health, Environments and Society, London School of Hygiene & Tropical Medicine, London, UK
3. Medical Research Council/Chief Scientist Office Social and Public Health Sciences Unit, University of Glasgow, Glasgow, UK
4. Centre for Development, Evaluation, Complexity and Implementation in Public Health Improvement, Cardiff University, Cardiff, UK
5. Northern Ireland Clinical Trials Unit, Belfast, UK
6. Health Economics Analysis and Research Methods Team, University College London, London, UK
7. Care and Public Health Research Institute (CAPHRI) School for Public Health and Primary Care, Maastricht University, Maastricht, the Netherlands
8. School of Social Sciences, Education and Social Work, Queen’s University Belfast, Belfast, UK
9. E-Health Unit, University College London, London, UK