1 Unit of Biostatistics, Epidemiology and Public Health, Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padua, Padua, Italy. dario.gregori@unipd.it.
2 Department of Otorhinolaryngology and Head and Neck Surgery (ENT), Maulana Azad Medical College and Associated Lok Nayak Hospital, New Delhi, India.
3 Unit of Biostatistics, Epidemiology and Public Health, Department of Cardiac, Thoracic, Vascular Sciences and Public Health, University of Padua, Padua, Italy.