1. Division of Endocrinology and Metabolism; Department of Internal Medicine; Hallym University College of Medicine; Seoul Korea
2. Division of Endocrinology and Metabolism; Department of Medicine; Kyung Hee University Hospital at Gangdong; Kyung Hee University School of Medicine; Seoul Korea
3. Department of Statistics; Dongguk University-Seoul; Seoul Korea
4. Division of Endocrinology and Metabolism; Department of Internal Medicine; School of Medicine Sungkyunkwan University; Seoul Korea