1. Centre of Public Health Sciences, School of Health Sciences, University of Iceland, Reykjavik, Iceland
2. Division of Health Information and Research, Directorate of Health, Reykjavik, Iceland
3. Department of Medicine, Landspitali University Hospital, Reykjavik, Iceland
4. Faculty of Medicine, School of Health Sciences, University of Iceland, Reykjavik, Iceland
5. Department of Epidemiology, Harvard TH Chan School of Public Health, Boston, Massachusetts, USA