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