1. Department of Family Medicine, College of Medicine and Cheonan Hospital, Soonchunhyang University, Cheonan-si, Republic of Korea
2. Chungnam Tobacco Control Center, College of Medicine, Soonchunhyang University, Cheonan-si, Republic of Korea
3. Department of Preventive Medicine, College of Medicine, Soonchunhyang University, Cheonan-si, Republic of Korea
4. Department of Clinical Pharmacology, College of Medicine, Soonchunhyang University, Cheonan-si, Republic of Korea
5. Department of Health Policy and Management, Seoul National University College of Medicine, Seoul, Republic of Korea