1. Department of Internal Medicine; Chungnam National University School of Medicine; Daejeon Korea
2. Department of Internal Medicine; Kangbuk Samsung Hospital; Sungkyunkwan University School of Medicine; Seoul Korea
3. Department of Internal Medicine; Seoul National University Bundang Hospital; Gyeonggi-do Korea
4. Department of Internal Medicine; Seoul Samsung Hospital; Sungkyunkwan University School of Medicine; Seoul Korea
5. Department of Internal Medicine; Seoul Asan Hospital; Seoul Korea
6. Department of Preventive Medicine; University of Ulsan College of Medicine; Ulsan Korea
7. Eulji University School of Medicine; Daejeon Korea