LAUSR

1Department of Public Health, College of Medicine, Yonsei University, Seoul, South Korea; 2Institute of Health Services Research, Yonsei University, Seoul, South Korea; 3Department of Preventive Medicine, College of Medicine, Yonsei University, Seoul, South Korea; 4Department of Surgery, College of Medicine, Yonsei University, Seoul, South Korea; 5Department of Internal Medicine, College of Medicine, Seoul National University, Seoul National University Hospital, Seoul, South Korea; 6Department of Surgery, School of Medicine, Sungkyunkwan University, Samsung Medical Center, Seoul, South Korea; 7Department of Otolaryngology–Head and Neck Surgery, College of Medicine, Inha University, Incheon, South Korea.