1. Department of Statistics, Informatics and Applications “G. Parenti,” University of Florence, Florence, Italy
2. Biostatistics Unit, Cancer Prevention and Research Institute (ISPO), Florence, Italy
3. Epidemiology Unit, Department of Preventive Medicine, Fondazione IRCCS (Istituto Di Ricovero e Cura a Carattere Scientifico) Ca` Granda, Ospedale Maggiore Policlinico, Milan, Italy
4. Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan, Italy