1. Institute of Environmental Medicine, Unit of Integrative Epidemiology, Karolinska Institutet , Nobels väg 13, 17177 Stockholm , Sweden
2. Center of Public Health Sciences, Faculty of Medicine, University of Iceland , Reykjavík , Iceland
3. NORMENT Centre, Institute of Clinical Medicine, University of Oslo and Division of Mental Health and Addiction, Oslo University Hospital , Oslo , Norway
4. KG Jebsen Centre for Neurodevelopmental Disorders, University of Oslo , Oslo , Norway
5. Department of Global Public Health, Karolinska Institutet , Stockholm , Sweden
6. Department of Public Health and Caring Sciences, Uppsala University , Uppsala , Sweden