1. University of Leipzig; Department of Medical Psychology and Medical Sociology; Leipzig Germany
2. University of Mainz; Division of Epidemiology and Health Services Research; Germany
3. University of Leipzig; Department of Otorhinolaryngology; Leipzig Germany
4. Hospital Martha-Maria; Department of Otorhinolaryngology; Halle-Dölau Germany
5. Hospital Dresden-Friedrichstadt; Department of Otorhinolaryngology; Dresden Germany
6. Hospital Elblandkliniken; Department of Otorhinolaryngology; Riesa Germany
7. Hospital Chemnitz; Department of Otorhinolaryngology; Chemnitz Germany
8. Martin-Luther-University; Department of Otorhinolaryngology; Halle Germany
9. Friedrich-Schiller-University; Department of Otorhinolaryngology; Jena Germany
10. Rehabilitation Clinic Sonnenbergklinik; Bad Sooden-Allendorf Germany
11. Helios Clinic; Department of Otorhinolaryngology; Erfurt Germany
12. Rehabilitation Clinic Bavaria; Kreischa Germany
13. Rehabilitation Clinic Brandis; Brandis Germany
14. Department of Non-Communicable Disease Epidemiology; London School of Hygiene and Tropical Medicine; London UK
15. University of Leipzig; Section of Phoniatrics and Audiology; Leipzig Germany