1. Department of Family Medicine; Kangwon National University Hospital; Korea
2. Department of Family Medicine and Health Promotion Center; Seoul National University Hospital; Korea
3. National Cancer Control Institute; National Cancer Center; Korea
4. Gangnam St. Mary Hospital; The Catholic University of Korea; Korea
5. Busan St. Mary's Medical Center; Korea
6. Kwangju Christian Hospital; Korea
7. St. Vincent's Hospital; The Catholic University of Korea; Korea