1. Department of Obstetrics and Gynecology, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Republic of Korea
2. Department of Pathology, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Republic of Korea
3. Department of Radiology, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Republic of Korea
4. Department of Clinical Epidemiology and Biostatics, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea