1. Department of ORL–Head & Neck Surgery and Audiology, Odense University Hospital, Odense
2. Department of Clinical Research, Department of Public Health, University of Southern Denmark, Odense
3. Research Unit for General Practice, Department of Public Health, University of Southern Denmark, Odense
4. Department for Database Section 1: Cardiovascular, Surgical and Acute Domains, Danish Clinical Registries, Odense
5. Otorhinolaryngology Department, Iuliu Hatieganu University of Medicine and Pharmacy Cluj-Napoca, Romania