Applying the health belief model to understand vaccine perceptions, barriers, and motivators and peer influence in an underserved community: A qualitative study.

Objectives: Vaccine uptake remains suboptimal in many communities and is influenced by individual beliefs, social norms, interpersonal relationships, and structural factors. Guided by the Health Belief Model (HBM), this study explored vaccine perceptions, barriers, motivators, peer influence, and interest in peer advocacy among young adults in a medically underserved U.S.-Mexico border community. Study design: We conducted eight virtual qualitative discussion sessions with 2-6 participants per session (total n = 27), recruited through university, community, and clinical partnerships. Sessions with only two participants were treated analytically as dyadic discussions because their interactional dynamics differed from those of larger focus groups. Methods: Discussions were audio-recorded, transcribed, and analyzed thematically using deductive HBM-informed and inductive coding approaches. Results: Participants generally described vaccines as beneficial preventive tools while also reporting concerns about side effects, misinformation, cost, access, and scheduling. Perceived benefits and barriers mapped directly onto HBM constructs, while institutional requirements and information seeking functioned as cues to action. Family and peer influence, social-media experiences, and willingness to participate in peer advocacy emerged as important interpersonal themes that extended beyond the traditional HBM framework. Participants in this sample frequently expressed interest in brief, practical, and supported peer-advocacy training. Conclusion: Participants described generally favorable vaccine attitudes alongside structural and informational barriers. Their reported interest in peer advocacy suggests an opportunity to develop and evaluate culturally and linguistically responsive, youth-centered training approaches. Because recruitment and incentives may have preferentially attracted individuals already interested in vaccination, advocacy willingness should be interpreted as a finding of this sample rather than generalized to young adults in the broader community.