1. Department of Internal Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea
2. Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
3. Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
4. Asan Diabetes Center, Asan Medical Center, Seoul, Korea