1. Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Korea.
2. Department of Pediatrics, Ewha Woman's University College of Medicine, Seoul, Korea.
3. Department of Pediatrics, Yonsei University College of Medicine, Severance Children's Hospital, Seoul, Korea.
4. Department of Pediatrics, Gangneung Asan Hospital, College of Medicine, University of Ulsan, Gangneung, Korea.
5. Department of Pediatrics, Chonbuk National University College of Medicine, Jeonju, Korea.
6. Department of Pediatrics, Soonchunhyang University College of Medicine, Seoul, Korea.
7. Department of Pediatrics, Yonsei University, Wonju College of Medicine, Wonju, Korea.
8. Department of Pediatrics, Pusan National University College of Medicine, Busan, Korea.
9. Department of Pediatrics, Ajou University College of Medicine, Suwon, Korea.
10. Department of Pediatrics, Inha University College of Medicine, Incheon, Korea.
11. Department of Pediatrics, Cheju National University College of Medicine, Jeju, Korea.
12. Department of Pediatrics, Inje University College of Medicine, Busan, Korea.
13. Department of Pediatrics, Chonnam National University Medical School, Hwasun, Korea.
14. Department of Pediatrics, Korea University College of Medicine, Seoul, Korea.
15. Department of Pediatrics, Kyungpook National University College of Medicine, Daegu, Korea.
16. Department of Pediatrics, Inje University College of Medicine, Ilsan, Korea.
17. Department of Pediatrics, Dankook University College of Medicine, Cheonan, Korea.
18. Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea.
19. Department of Pediatrics, Chungbuk National University College of Medicine, Cheongju, Korea.
20. Division of Cardiovascular and Rare Disease, National Institute of Health, Korea Centers for Disease Control and Prevention, Cheongwon, Korea.