1. Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea.
2. Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Korea.
3. Department of Internal Medicine, Keimyung University School of Medicine, Daegu, Korea.
4. Department of Internal Medicine, Yeungnam University College of Medicine, Daegu, Korea.
5. Department of Internal Medicine, Dongguk University School of Medicine, Gyeongju, Korea.
6. Department of Internal Medicine, Gyeongsang National University Hospital, Jinju, Korea.
7. Department of Internal Medicine, Soonchunhyang University Gumi Hospital, Gumi, Korea.