1Department of Internal Medicine, Inha University School of Medicine, Incheon, Korea.
2Department of Preventive and Social Mecine, Inha University School of Medicine, Incheon, Korea.
3Department of Internal Medicine, University of Ulsan College of Medicine, Seoul, Korea. yskoh@amc.seoul.kr
4Department of Internal Medicine, Sungkyunkwan University School of Medicine, Suwon, Korea.
5Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea.
6Department of Internal Medicine, The Catholic University of Korea College of Medicine, Seoul, Korea.
7Department of Anesthesiology and Pain Medicine, Chonnam National University Medical School, Gwangju, Korea.
8Department of Internal Medicine, Hallym Univerity College of Medicine, Chuncheon, Korea.
9Department of Internal Medicine, Inje University College of Medicine, Busan, Korea.