1. Operative Unit of Hygiene and Public Health-Forlì and Cesena, Department of Public Health, Romagna Local Health Authority, 47522 Cesena, Italy
2. Unit of Hygiene and Medical Statistics, Department of Biomedical and Neuromotor Sciences, University of Bologna, 40126 Bologna, Italy
3. Operative Unit of Hygiene and Public Health-Ravenna, Department of Public Health, Romagna Local Health Authority, 48121 Ravenna, Italy
4. Operative Unit of Hygiene and Public Health-Rimini, Department of Public Health, Romagna Local Health Authority, 47924 Rimini, Italy