1. Department of Otolaryngology–Head and Neck Surgery, Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan
2. Otitis Media Research Center, Department of Otolaryngology, University of Minnesota, Minneapolis, Minnesota
3. Department of Otolaryngology, Kagawa Prefectural Central Hospital, Kagawa, Japan
4. Department of Otolaryngology, Okayama Saiseikai General Hospital, Okayama, Japan
5. Department of Otolaryngology, Tsuyama Central Hospital, Tsuyama, Japan
6. International Hearing Foundation, Minneapolis, Minnesota
7. Minnesota Ear Head and Neck Clinic, Minneapolis, Minnesota