1. 1Department of Internal Medicine, Institute of Evidence-Based Medicine, Wonju Severance Christian Hospital, Yonsei University Wonju College of Medicine, Wonju, Gangwon-do, South Korea
2. 2Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Gangnam-gu, Seoul, South Korea
3. 3Department of Internal Medicine, Seoul National University College of Medicine, Jongno-gu, Seoul, South Korea