1. Division of Medicine, Oslo University Hospital, Oslo, Norway
2. Department of Community Medicine, University of Oslo, Oslo, Norway
3. Center for Community Research, DePaul University Chicago, USA
4. The Norwegian Medical Association, Journal of the Norwegian Medical Association, Oslo, Norway
5. Oslo Centre for Biostatistics and Epidemiology, Oslo University Hospital, Oslo, Norway
6. Faculty of Fundamental Science, Gediminas Technical University, Vilnius, Lithuania
7. Department of Paediatrics, Oslo University Hospital, Rikshospitalet, Oslo, Norway
8. Department of Behavioral Medicine, University of Oslo, Oslo, Norway