While adolescent birth rates are at their lowest in years across the nation, key racial-ethnic, economic, and geographic disparities remain. These differences suggest a need to continue building the evidence base for teen pregnancy prevention (TPP) programs and ensure findings reach those working in the field. The Office of Adolescent Health (OAH), located within the Department of Health and Human Services (HHS), strives to learn more about what works, for whom, and under what conditions in an attempt to reduce teen pregnancies across all populations and subpopulations. Accordingly, OAH funded a special supplement of the American Journal of Public Health that features the results of OAH-funded research conducted from 2010 to 2015. The supplement, which includes contributions from Mathematica Policy Research experts, focuses on findings from impact evaluations of rigorous studies of programs designed to reduce risky sexual behaviors and pregnancy among adolescents. 
OAH required grantees to use rigorous evaluation methods to assess the effectiveness of TPP programs. Mathematica provided evaluation technical assistance to a group of more than 40 TPP program grantees charged with designing and implementing high quality, rigorous evaluations and oversaw development of the supplement. The journal supplement highlights findings from a subset of grantees, including discussions of challenges and lessons learned.
Mathematica authors made several significant contributions:
- An editorial on how the OAH impact studies are building the evidence base and a paper on impacts from a rigorous study of a middle school curriculum module by Associate Director of Human Services Brian Goesling
- An editorial on the importance of small or insignificant impacts by Senior Researcher Russell Cole
- A series of editorials on evaluation technical assistance by Associate Director of Human Services Jean Knab, and Senior Researchers Russell Cole and Susan Zief that describe OAH’s support of research that meets HHS evidence standards, the framework for evaluation technical assistance, and challenges and lessons learned from providing large-scale technical assistance in this effort
