1. Department of Preventive Medicine and Public Health, Food Sciences, Toxicology, and Legal Medicine, School of Pharmacy , University of Valencia , Avenida Vicente Andres Estellés s/n, Burjassot, 46100 Valencia , Spain
2. CIBER of Epidemiology and Public Health (CIBERESP). Av. Monforte de Lemos, 3-5. Pabellón 11. Planta 0 28029 Madrid
3. Department of Statistics, Computer Science and Applications “G. Parenti” , University of Florence , Florence , Italy
4. Department of Health Sciences , University of Florence , Viale GB Morgagni 48, 50134 Florence , Italy