1. Declines in state teen birth rates by race and Hispanic origin. NCHS data brief, no. 123;Hamilton,2013
2. North Carolina youth risk behavior survey;North Carolina Department of Public Instruction,2012
3. Youth risk behavior surveillance system (YRBSS);Centers for Disease Control (CDC),2012
4. Martin JA, Hamilton BE, Ventura SJ, et al. Births: Final data for 2010. National Vital Statistics Reports 2012;61 (August 28, 2012). U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Health Statistics, National Vital Statistics System. Available at: http://www.cdc.gov/nchs/data/nvsr/nvsr61/nvsr61_01.pdf#table12.
5. Social learning theory;Bandura,1977