1. Centre of Public Health Sciences; University of Iceland; Reykjavık Iceland
2. Division of Clinical Cancer Epidemiology; Department of Oncology-Pathology, Karolinska Institutet; Stockholm Sweden
3. Palliative Centre; Lund University; Lund Sweden
4. Division of Clinical Cancer Epidemiology, Department of Oncology; Sahlgrenska Academy, University of Göteborg; Göteborg Sweden