1. Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
2. Department of Epidemiology and Health Services Research, Centre for Primary Care and Public Health (Unisanté), University of Lausanne, Lausanne, Switzerland
3. Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, Maryland
4. Department of Family, Population and Preventive Medicine, Stony Brook Cancer Center, Stony Brook University, Stony Brook, New York, USA
5. Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy