1. Department of Gastroenterology, Asan Liver Center; Asan Medical Center; University of Ulsan College of Medicine; Seoul Republic of Korea
2. Department of Biostatistics and Clinical Epidemiology; Asan Medical Center; University of Ulsan College of Medicine; Seoul Republic of Korea
3. Department of Oncology; Asan Medical Center; University of Ulsan College of Medicine; Seoul Republic of Korea
4. Department of Internal Medicine; Vievisnamuh Hospital; Seoul Republic of Korea