1. Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital of Marburg University of Gießen and Marburg Marburg Germany
2. Department of International Health, CAPHRI ‐ Care and Public Health Research Institute Maastricht University Maastricht The Netherlands
3. Department of Pediatrics, Faculty of Medicine and University Hospital Cologne University of Cologne Cologne Germany
4. Department of Otorhinolaryngology, Head and Neck Surgery University of Cologne Cologne Germany
5. Global Health Cluster, Division for Health Services Norwegian Institute of Public Health Oslo Norway
6. Department of Otorhinolaryngology, Head and Neck Surgery University of Göttingen Göttingen Germany