1. Ullevål University Hospital, Oslo, Norway, Sahlgrenska Academi, Göteborgs University, Göteborg, Sweden.
2. Norwegian Institute of Public Health, Oslo, Norway, Sahlgrenska Academi, Göteborgs University, Göteborg, Sweden.
3. Akershus University Hospital, Oslo, Norway, Sahlgrenska Academi, Göteborgs University, Göteborg, Sweden.