Abstract
INTRODUCTION: Inclusion science has demonstrated the relative value of recruitment strategies, including engaging people from the intended study population to help shape recruitment materials. Yet, these studies rarely describe specific design and content features of visual recruitment materials. We aimed to experimentally test the effects of one simple design feature - the inclusion of a photograph of the principal investigator in visual recruitment materials - on willingness to participate in research. METHODS: We conducted this experiment in community settings, tabling at community events (community health fairs, back-to-school events, and sporting events), from December 2023 to January 2025. 192 people completed the experiment. RESULTS: The three-factor interaction of photograph type, similarity to researcher, and researcher credibility had a significant effect on willingness to participate in a brain health research study. DISCUSSION: Results demonstrate strategies for improving the effectiveness of advertisements. First, findings demonstrate the role of researcher credibility and similarity to researcher in volunteers' consideration of participation. Second, results suggest the use of researcher photographs in recruitment materials.