1. Department of Breast and Endocrine Surgery, Akershus University Hospital, Lorenskog, Norway
2. Institute of Clinical Medicine, University of Oslo, Oslo, Norway
3. The Norwegian Knowledge Centre for the Health Services, Oslo, Norway
4. Division of Infectious Disease Control, National Institute of Public Health, Oslo, Norway
5. Department of Chemistry, Biotechnology and Food Sciences, Norwegian University of Life Sciences, Aas, Norway
6. Institute of Health Promotion, Akershus University Hospital, Lorenskog, Norway