1. Department of Otorhinolaryngology, Kristianstad Hospital, Kristianstad, Sweden
2. Department of Otorhinolaryngology, Anaesthetics, Operations and Specialty Surgery Center, Linkoping, Sweden
3. Division of Sensory Organs and Communication, Department of Biomedical and Clinical Sciences, Linkoping University, Sweden
4. Department of Otorhinolaryngology and Head and Neck Surgery, Skane University Hospital, Lund, Sweden
5. Department of Clinical Sciences, Lund University, Lund, Sweden