1. Institute of Public Health and Medical Service, Seoul National University Hospital, Seoul, Korea.
2. Department of Pediatrics, Seoul National University Hospital, Seoul, Korea.
3. Department of Medical Administration, Daejeon Health Sciences College, Daejeon, Korea.
4. Department of Nursing Science, Shinsung University, Dangjin, Korea.
5. College of Nursing, Seoul National University, Seoul, Korea.
6. Public Health Medical Service, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul National University College of Medicine, Seoul, Korea.
7. Institute of Health Policy and Management, Medical Research Center, Seoul National University, Seoul, Korea.