Sunyoung Kim1, Chang Won Won2, Hyuk Ga3. 1. Department of Family Medicine, College of Medicine, Kyung Hee University, Kyung Hee Medical Center, Seoul, Korea; Department of Medicine, The Graduate School, Ewha Womans University, Seoul, Korea. 2. Department of Family Medicine, College of Medicine, Kyung Hee University, Kyung Hee Medical Center, Seoul, Korea. 3. Department of Family Medicine, Institute of Geriatric Medicine, Incheon Eun-Hye Hospital, Incheon, Korea.