1. Department of Gastroenterology Chung‐Ang University Gwangmyeong Hospital Gwangmyeong Korea
2. Department of Internal Medicine Yonsei University College of Medicine Seoul Korea
3. Department of Gastroenterology Ajou University School of Medicine Suwon Korea
4. Department of Internal Medicine Hanyang University Hospital, Hanyang University College of Medicine Seoul Korea
5. Department of Internal Medicine Seoul National University College of Medicine, Seoul National University Bundang Hospital Seongnam Korea
6. Department of Internal Medicine Chung‐Ang University Hospital Seoul Korea
7. Health Insurance Review and Assessment Service Seoul South Korea