1. From the Public Health Research Institute, National Medical Center
2. Department of Pediatrics, Konkuk University Medical Center
3. Department of Pediatrics, National Medical Center
4. Department of Pediatrics, Korea University Anam Hospital
5. Center for Public Health Data Analytics, National Medical Center, Seoul, Republic of Korea
6. Department of Pediatrics, Seoul National University College of Medicine, Seoul, Republic of Korea
7. Department of Pediatrics, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.