1. Centre for Clinical Research, Dalarna, Falun, Sweden,
2. Department of Public Health and Community Medicine/Public Health Epidemiology Unit, The Sahlgrenska Academy, University of Gothenburg, Sweden
3. Department of Primary Health Care, The Sahlgrenska Academy, Sweden
4. Department of Clinical Neuroscience, Section for Psychiatry, Huddinge, Karolinska Institute, Stockholm, Sweden