1. Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
2. Department of Laboratory Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
3. Department of Laboratory Medicine, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea.
4. Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.