1. Department of Pediatrics, Pusan National University Children’s Hospital, Pusan National University College of Medicine, Yangsan, Korea.
2. Department of Pediatrics, Chungbuk National University College of Medicine, Cheongju, Korea.
3. Department of Pediatrics, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
4. Department of Pediatrics, Gyeongsang National University School of Medicine, Gyeongsang Institute of Sciences, Gyeongsang National University Hospital, Jinju, Korea.
5. Department of Occupational and Environmental Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
6. Division of Gastrointestinal Surgery, Department of Surgery, Pusan National University Yangsan Hospital, Yangsan, Korea.