1. Section for Pharmacology, Institute of Medicine, University of Bergen, 5021 Bergen, Norway
2. Department of Public Health and Primary Health Care, University of Bergen, 5020 Bergen, Norway
3. Bevital AS, Laboratory Building, Haukeland University Hospital, 5021 Bergen, Norway
4. Institute of Clinical Biochemistry, Faculty of Medicine, University of Oslo and Department of Medical Biochemistry, Rikshospitalet-Radiumhospitalet Medical Centre, 0022 Oslo, Norway
5. The Cancer Registry of Norway, Institute of Population-based Cancer Research, 0304 Oslo, Norway
6. Laboratory of Clinical Biochemistry, Haukeland University Hospital, 5021 Bergen, Norway