1. Department of Biomaterials, Institute of Clinical Sciences, Sahlgrenska Academy; University of Gothenburg; Gothenburg
2. Department of Otorhinolaryngology; NU- Hospital Group; Trollhättan
3. Department of Otorhinolaryngology; Mälarsjukhuset Hospital; Eskilstuna
4. Department of Otorhinolaryngology; Sahlgrenska University Hospital; Gothenburg
5. Department of Otorhinolaryngology; Skåne University Hospital; Lund
6. Department of Otorhinolaryngology; Karolinska University Hospital; Stockholm
7. Department of Clinical Sciences, Otorhinolaryngology; Umeå University; Umeå
8. Department of Surgical Science, Otorhinolaryngology; Uppsala University Hospital; Sweden