1. Aberdeen Health Psychology Group, Institute of Applied Health Sciences, College of Life Sciences and Medicine, University of Aberdeen, Foresterhill, Aberdeen, UK
2. Department of Clinical, Educational and Health Psychology, University College London, London, UK
3. Department of Kinesiology, University of Rhode Island, Kingston, RI, USA
4. Department of Psychology, University of Minnesota, Minneapolis, MN, USA
5. Institute of Public Health, University of Cambridge, Forvie Site, Cambridge, UK