1. Health and Well-Being Promotion Unit, Finnish Institute for Health and Welfare, P.O. Box 30, FI-00271, Helsinki, Finland
2. Institute for Mental Health Policy Research, and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
3. Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada
4. Centre of Excellence in Game Culture Studies, University of Turku, Turku, Finland
5. Gamification Group, Faculty of Information Technology and Communication Sciences, Tampere University, Tampere, Finland
6. Department of Psychology and Speech-Language Pathology, University of Turku, Turku, Finland
7. Faculty of Medicine, University of Helsinki, Finland