1. Department of Otorhinolaryngology, Head and Neck Surgery, Sahlgrenska University Hospital and Institute of Clinical Sciences, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden
2. Department of Otorhinolaryngology, Ryhov County Hospital, Jönköping, Sweden
3. Institute of Clinical Sciences, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden and Sheikh Khalifa Medical City, Ajman, United Arab Emirates