1. Department of Social Sciences, University of Eastern Finland, Kuopio, Finland.
2. Department of Social Research, University of Turku, Turku, Finland.
3. Department of Adolescent Psychiatry, University of Turku and Turku University Hospital, Turku, Finland.
4. Department of Social Sciences and Institute of Clinical Medicine, Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.