1. Department of Family Medicine, Pusan National University Hospital, Busan, South Korea
2. Busan Tobacco Control Center, Busan, South Korea
3. Biomedical Research Institute, Pusan National University Hospital, Busan, South Korea
4. Family Medicine Clinic, Obesity, Metabolism and Nutrition Center and Research Institute of Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, South Korea
5. Medical Education Unit and Medical Research Institute, Pusan National University School of Medicine, Yangsan, South Korea