1. Institute of Otolaryngology; Department of Otolaryngology-Head and Neck Surgery, Chinese PLA General Hospital; Beijing China
2. Department of Epidemiology Research; Toho University; Tokyo Japan
3. Division of Allergy, Department of Medical Subspecialties; National Center for Child Health and Development; Tokyo Japan
4. Medical Support Center for Japan Environment and Children's Study, National Center for Child Health and Development; Tokyo Japan