1. Department of Screening Based-research, The Cancer Registry of Norway, 0304 Oslo, Norway
2. Department of Radiology, University of North Carolina at Chapel Hill, 27599, USA
3. Cancer Epidemiology Unit, University Institute of Social and Preventive Medicine, Lausanne, Switzerland
4. Health Services and Economics Branch, Applied Research Program, Division of Cancer Control and Population Sciences, National Cancer Institute, Bethesda, Maryland 20892–7344, USA
5. Department of Public Health, NETB, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands