1. Department of Preventive Medicine, School of Medicine, Kyung Hee University, Seoul, Korea.
2. Cancer Policy Branch, National Cancer Control Institute, National Cancer Center, Goyang, Korea.
3. Department of Medical Education and Humanities, School of Medicine, Kyung Hee University, Seoul, Korea.
4. Cancer Registration and Statistic Branch, National Cancer Control Institute, National Cancer Center, Goyang, Korea.
5. Department of Pediatrics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Korea.