1. Department of Pediatrics, Medical Research Institute of Pusan National University Hospital, Pusan National University School of Medicine, Busan, Korea.
2. Department of Pediatrics, Samyook Medical Center, Seoul, Korea.
3. Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
4. Environmental Health Center for Atopic Diseases, Samsung Medical Center, Seoul, Korea.
5. Department of Health Administration and Management, Soonchunhyang University College of Medical Science, Asan, Korea.
6. Department of Pediatrics, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
7. Department of Pediatrics, Inje University College of Medicine, Seoul, Korea.
8. Department of Occupational and Environmental Medicine, College of Medicine, Dankook University, Cheonan, Korea.
9. Department of Pediatrics, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul, Korea.
10. Department of Pediatrics, CHA University School of Medicine, Seongnam, Korea.
11. Department of Information and Statistics, Korea National Open University, Seoul, Korea.
12. Department of Preventive Medicine, Dankook University College of Medicine, Cheonan, Korea.
13. Biostatistics and Clinical Epidemiology Center, Research Institute for Future Medicine, Samsung Medical Center, Seoul, Korea.