1. Faculty of Medicine and Health Sciences, University of Antwerp, Belgium
2. Institute of Health Studies, HAN University of Applied Sciences, Nijmegen, the Netherlands
3. European Institute for ORL, Sint-Augustinus Hospital, Antwerp, Belgium
4. Faculty of Education, Health & Social Work, University College Ghent, Belgium
5. Faculty of Health Care, HU University of Applied Sciences Utrecht, the Netherlands
6. Faculty of Humanities, University of Utrecht, the Netherlands
7. Department of Otolaryngology, University Medical Center Utrecht, the Netherlands
8. Department of Otorhinolaryngology and Head & Neck Surgery, Antwerp University Hospital, Belgium
9. Faculty of Medicine & Health Sciences, University of Ghent, Belgium