[1] Inha University,Department of Family Medicine, School of Medicine
[2] Cancer Epidemiology Branch,Health Promotion Center, Department of Family Medicine
[3] Research Institute,Department of Preventive Medicine
[4] Smoking Cessation Clinic,Department of Obstetrics and Gynecology, School of Medicine
[5] Family Medicine Clinic,undefined
[6] and Center for Cancer Prevention and Detection,undefined
[7] Hospital,undefined
[8] National Cancer Center,undefined
[9] Seoul National University Hospital,undefined
[10] Seoul National University College of Medicine,undefined
[11] Ewha Womans University,undefined