1 Division of Endocrinology and Metabolism, Department of Internal Medicine, Myongji Hospital, Seonam University College of Medicine, Gyeonggi-do, Republic of Korea.
2 Department of Medical Statistics, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
3 Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
4 Division of Endocrinology and Metabolism, Department of Internal Medicine, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
5 Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea. drkwon@catholic.ac.kr.
6 Division of Endocrinology and Metabolism, Department of Internal Medicine, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea. drkwon@catholic.ac.kr.