1. School of Social and Political Sciences, University of Glasgow, Glasgow G12 8RS, UK
2. School of Psychological Sciences and Health, University of Strathclyde, Glasgow G1 1QE, UK
3. Retired—Previously MRC/CSO Social and Public Health Sciences Unit, School of Health and Wellbeing, University of Glasgow, Glasgow G3 7HR, UK
4. Institute for Social Marketing and Health, University of Stirling, Stirling FK9 4LA, UK