1. Department of Educational & Social Policy, University of Macedonia, Thessaloniki, Greece
2. Department of Hearing & Speech Sciences, University of Maryland, College Park
3. 1st Otolaryngology Department, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Greece
4. 1st University Otolaryngology Clinic of AHEPA Hospital, School of Medicine, Aristotle University of Thessaloniki, Greece