1. Department of Obstetrics and Gynecology, Peking University Ninth School of Clinical Medicine, Beijing Shijitan Hospital, Beijing, China
2. National Clinical Research Center for Otolaryngologic Diseases, Beijing, China
3. State Key Lab of Hearing Science, Ministry of Education, Beijing, China
4. Senior Department of Otolaryngology–Head & Neck Surgery, Sixth Medical Center of PLA General Hospital, Beijing, China
5. Peking University Fifth School of Clinical Medicine, Beijing Hospital, Beijing, China
6. Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Beijing, China
7. Department of Otorhinolaryngology, Head and Neck Surgery, Chinese University of Hong Kong, Hong Kong, China