Insights From the Health Profession Opportunity Grant Program's Three-Armed, Multi-Site Experiment for Policy Learning and Evaluation Practice.

Administered by the Office of Family Assistance in the U.S. Department of Health and Human Services' Administration for Children and Families (ACF), the Health Profession Opportunity Grants (HPOG) Program provided education and training to Temporary Assistance for Needy Families (TANF) recipients and other adults with low incomes for occupations in the healthcare field. The impact evaluation for the first cohort of grantees (HPOG 1.0) leveraged the program's implementation across many locations, using a three-armed evaluation design (including a second treatment arm) in some places, as a way to examine whether any of three selected program components, or enhancements, contributed to the program's overall impact. This article tells the story of the evaluation and draws lessons from that experience, discussing implications for future implementation of multi-armed experiments in a multi-site evaluation.