1. Department of Internal Medicine, Daegu Catholic University College of Medicine, Daegu, South Korea,
2. Department of Internal Medicine, Inje University College of Medicine, Busan, South Korea,
3. Department of Hematology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea,
4. Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, South Korea,
5. Department of Internal Medicine, Yeungnam University College of Medicine, Daegu, South Korea,
6. Department of Internal Medicine, Hallym University College of Medicine, Anyang, South Korea