1. Department of Clinical Sciences and Community Health; Università degli Studi di Milano; Milan Italy
2. Department of Epidemiology; IRCCS-Istituto di Ricerche Farmacologiche “Mario Negri”; Milan Italy
3. Department of Surgery and Translational Medicine; Clinica Otorinolaringoiatrica; Università degli Studi di Milano Bicocca; Milan Italy
4. Department of Medicine and Community Health; Institute of Social and Preventive Medicine (IUMSP) Lausanne University Hospital; Lausanne Switzerland