1. Department of Speech and Hearing Sciences at Ookawa International University of Health and Welfare Ookawa Fukuoka Japan
2. Department of Speech and Hearing Sciences at Narita International University of Health and Welfare Narita Japan
3. The Voice and Dizziness Clinic Futakotamagawa Otolaryngology Setagaya Japan
4. Tokyo Voice Center, Sanno Hospital International University of Health and Welfare Minato‐ku Japan
5. Mita Hospital International University of Health and Welfare Minato‐ku Japan