1. Health Screening and Promotion Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
2. Department of Internal Medicine, National Medical Center, Seoul, Korea
3. Department of Internal Medicine, Wonkwang University College of Medicine and Digestive Disease Research Institute, Iksan, Korea
4. Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea
5. Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea
6. Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
7. Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea