1. ENT Department, Regional Hospital, Endach 27, 6330 Kufstein, Austria
2. Pradlerstraße 4, 6020 Innsbruck, Austria
3. University ENT Hospital, Paracelsus Private Medical University, Müllner Hauptstraße 48, 5020 Salzburg, Austria
4. University Hospital of Otorhinolaryngology, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria
5. ENT Department, S.D. Asfendiyarov Kazakh National Medical University, Almaty 050012, Kazakhstan
6. Department of Medical Statistics, Informatics and Health Economics, Innsbruck Medical University, 6020 Innsbruck, Austria