1. Division of Endocrinology and Metabolism, Department of MedicineKorea University Guro Hospital Seoul Republic of Korea
2. Division of Endocrinology and Metabolism, Department of Medicine, Samsung Medical CenterSungkyunkwan University School of Medicine Seoul Republic of Korea
3. Department of BiostatisticsThe Catholic University of Korea Seoul Republic of Korea
4. Department of Statistics and Actuarial ScienceSoongsil University Seoul Republic of Korea
5. Division of Endocrinology and Metabolism, Department of MedicineKyung Hee University School of Medicine Seoul Republic of Korea
6. Department of Clinical Research Design and EvaluationSamsung Advanced Institute for Health Sciences and Technology Seoul Republic of Korea