1. Department of Oncology, Oslo University Hospital, Norwegian Radium Hospital, P.O. Box 5960, Nydalen, 0424 Oslo, Norway
2. Institute of Clinical Medicine, University of Oslo, P.O. Box 1078, Blindern, 0316 Oslo, Norway
3. Faculty of Health Sciences, Department of Nursing, Oslo and Akershus University College of Applied Sciences, St. Olavs plass, P.O. Box 4, 0130 Oslo, Norway
4. Institute of Health and Society, Department of Health Sciences, University of Oslo, P.O. Box 1089, Blindern, 0317 Oslo, Norway