1. Department of Pediatrics, Inha University College of Medicine, Incheon, Korea.
2. Korea Hemophilia Foundation, Seoul, Korea.
3. Department of Pediatrics, Kyungpook National University Hospital, Daegu, Korea.
4. Department of Pediatrics, Daegu Catholic University Hospital, Daegu, Korea.
5. Department of Pediatrics, University of Ulsan College of Medicine, Ulsan, Korea.