1. Department of Health Promotion and DevelopmentFaculty of Psychology, University of Bergen Christiesgate 13 5015 Bergen Norway
2. Department of Psychological MedicineInstitute of Psychiatry, King's College London Cutcombe Road SE5 9RJ London UK
3. Department of Public Mental HealthDivision of Mental HealthNorwegian Institute of Public Health Christiesgate 13 5015 Bergen Norway