1. Division of Infectious Diseases; Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine; Seoul South Korea
2. Department of Occupational and Environmental Medicine; Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine; Seoul South Korea
3. Center for Cohort Studies; Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine; Seoul South Korea
4. Department of Clinical Research Design & Evaluation; SAIHST, Sungkyunkwan University; Seoul South Korea