1. Division of Endocrinology and Metabolism, Department of Internal Medicine, Daejeon Eulji Medical Center, Eulji University School of Medicine, Daejeon, Korea.
2. Department of Endocrinology and Metabolism, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea.
3. Department of Endocrinology and Metabolism, Daejeon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Daejeon, Korea.
4. Department of Endocrinology and Metabolism, Chungnam National University Hospital, Chungnam National University College of Medicine, Daejeon, Korea.
5. Department of Endocrinology and Metabolism, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan, Korea.
6. Department of Endocrinology and Metabolism, Chungbuk National University Hospital, Chungbuk National University College of Medicine, Cheongju, Korea.