1. Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
2. Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
3. Department of Internal Medicine, Heart Research Center, Chonnam National University, Gwangju, Korea.
4. Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.
5. Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
6. Department of Internal Medicine, The Catholic University of Korea, Seoul, Korea.
7. Department of Internal Medicine, School of Medicine, Sungkyunkwan University, Seoul, Korea.
8. Department of Internal Medicine, University of Ulsan College of Medicine, Seoul, Korea.
9. Department of Internal Medicine, Chungbuk National University College of Medicine, Cheongju, Korea.
10. Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Korea.