| Affiliation: | 1. Department of Clinical Sciences/Otorhinolaryngology, Ume? University, Ume?, Sweden;2. Department of Surgical and Perioperative Sciences/Surgery, Ume? University, Ume?, Sweden;3. Department of Odontology/Oral and Maxillofacial Radiology, Ume? University, Ume?, Sweden;4. Department of Ume? School of Business and Economics/Statistics, Ume? University, Ume?, Sweden;5. Department of Public Health and Clinical Medicine/Epidemiology and Global Health, Ume? University, Ume?, Sweden;6. Department of Public Health and Clinical Medicine/Medicine, Ume? University, Ume?, Sweden |
