1. Department of Otorhinolaryngology and Head and Neck Surgery, Ruhr University Bochum, St. Elisabeth-Hospital, Bochum, Germany;
2. Upper Airways Research Laboratory and ENT-Department, Ghent University Hospital, Ghent, Belgium;
3. Department of Epidemiology, IQVIA, Frankfurt, Germany;
4. Department of Otorhinolaryngology, Head and Neck Surgery, Solingen Municipal Hospital, Solingen, Germany