1. Department of Family Medicine, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Korea.
2. Department of Family Medicine, Seoul National University College of Medicine, Seoul, Korea.
3. Department of Biomedicine & Health Sciences, College of Medicine, Catholic University of Korea, Seoul, Korea.
4. Department of Internal Medicine, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Korea.
5. Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
6. Department of Statistics and Actuarial Science, Soongsil University, Seoul, Korea.