1. Department of CLINTEC, Division of Ear, Nose and Throat Diseases, Karolinska Institutet, SE-141 86 Stockholm, Sweden
2. Department of Audiology and Neurotology, Karolinska University Hospital, SE-118 95 Stockholm, Sweden
3. Department of CLINTEC, Division of Audiology, Karolinska Institutet, SE-141 52 Huddinge, Sweden
4. Department of Otorhinolaryngology, Central Hospital, SE-652 30 Karlstad, Sweden
5. Faculty of Medicine and Health, Medicine and Health, Örebro University, SE-701 82 Örebro, Sweden