1. Department of Internal Medicine; Asan Medical Center; University of Ulsan College of Medicine; Seoul South Korea
2. Department of Internal Medicine; International St. Mary's Hospital; Catholic Kwandong University College of Medicine; Incheon South Korea
3. Department of Health Promotion; Seoul St. Mary's Hospital; College of Medicine; The Catholic University of Korea; Seoul South Korea
4. Department of Internal Medicine; Seoul St. Mary's Hospital; College of Medicine; The Catholic University of Korea; Seoul South Korea