The Pregnancy Risk Assessment Monitoring System (PRAMS) is a multi-mode survey providing state-specific, population-based data on maternal attitudes and experiences before, during, and after pregnancy. While overall response rates for the survey are high, participation is significantly lower among minority populations, including African Americans. Previous studies have shown the use of incentives increases participation among minority populations in PRAMS. Less is known about the impact of incentives on sample representativeness and cost effectiveness.
The PRAMS administration in Kentucky found response rates for their oversample of African American mothers (51%) was significantly lower than non-African American mothers (63%). Lower response rates can lead to higher levels of non-response bias in results.
In 2018, Kentucky worked with the CDC to conduct an experiment to increase participation among African American mothers. Sample was randomly assigned to either a control group, which received the standard $5 upfront cash incentive and a $10 gift card upon completing the survey, or an experimental group, which received the same incentive plus an additional $10 gift card after survey completion.
Results show response rates among African Americans in the experimental group were significantly higher than the control group (73% to 51%). Experimental group respondents more accurately reflected the population of the state for low birth weight and percentage of adolescent mothers. Costs analysis shows a lower cost per complete among the experimental group, driven by a significantly higher response to the first mailing. Future analysis will compare survey response distributions and item non-response between the two groups.
Our findings help other states improve their PRAMS data collection protocols when targeting minority or other hard to reach respondents. The study also demonstrates how incentives can increase sample representativeness among minority populations and how they can decrease the cost per survey despite the additional cost of incentives.