1. Department of Otolaryngology Örebro University Hospital Örebro Sweden
2. School of Medical Sciences Örebro University Örebro Sweden
3. Department of Otolaryngology Vastmanland County Hospital Västerås Sweden
4. Clinical Epidemiology and Biostatistics, School of Medical Sciences Örebro University Örebro Sweden
5. Department of Oto‐Rhino‐Laryngology, Head and Neck Surgery Karolinska University Hospital Stockholm Sweden