1. Department of Epidemiology and Biostatistics, Graduate School of Public Health, Yonsei University, Seoul, Korea.
2. School of Public Health, Health Sciences University of Mongolia, Ulaanbaatar, Mongolia.
3. Department of Medical Informatics, Graduate School of Public Health, Yonsei University, Seoul, Korea.
4. Department of Obstetrics and Gynecology, Kangnam Hospital, Catholic University, Seoul, Korea.
5. Institute for Health Promotion, Graduate School of Public Health, Yonsei University, Seoul, Korea.
6. Department of Health Promotion and Education, Graduate School of Public Health, Yonsei University, Seoul, Korea.