1. Biostatistics Unit, ISPO Cancer Research and Prevention Institute, Via Cosimo il Vecchio 2, 50139 Florence, Italy
2. Department of Statistics ‘G. Parenti’, University of Florence, Italy; Director, Biostatistics Unit, ISPO Cancer Research and Prevention Institute, Via Cosimo il Vecchio 2, 50139 Florence, Italy
3. Local Health Authority, Ospedale Santa Maria Annunziata, Via dell'Antella, 58, 50012 (Bagno a Ripoli) Florence, Italy
4. Analytical Cytology and Biomolecular Unit, ISPO Cancer Research and Prevention Institute, Via Cosimo il Vecchio 2, 50139 Florence, Italy
5. Unit of Clinical and Descriptive Epidemiology, ISPO Cancer Research and Prevention Institute, Via Cosimo il Vecchio 2, 50139 Florence, Italy