Evaluating the Impact of the Campaign's Heavy-Up Advertising on Initial COVID-19 Vaccine Uptake.

To address vaccine hesitancy, the U.S. Department of Health and Human Services (HHS) launched the "" COVID-19 public education campaign (the Campaign) in 2021 to promote vaccine confidence and increase vaccine uptake. The Campaign introduced a heavy-up media strategy to enhance its reach and engagement with its vaccine hesitant audience. This approach complemented the Campaign's national media strategy while delivering an additional advertising dose to select priority designated market areas (DMAs) - that is, media markets - each month. We examine the relationship between the Campaign's heavy-up strategy and initial COVID-19 vaccine uptake from August to December 2021. A stacked difference-in-differences (DID) analysis compared initial COVID-19 vaccine uptake between DMAs that received heavy-up (treatment) and DMAs that did not (control). The Campaign's short-term heavy-up advertising strategy was associated with increased initial vaccine uptake in treatment DMAs. These results provide valuable insights for public health campaign strategy and evaluation, highlighting the effectiveness of increasing campaign dose in select markets to address vaccine hesitancy and improve public health outcomes.