Pre-Post Evaluation of a Sun Safety Social Media Campaign for Young Adults to Reduce Skin Cancer Risk

Background: Social media is a prevalent source of health information for young adults and offers a scalable platform for skin cancer prevention messaging, including sun safety. Despite high awareness among young adults that UV radiation is a potent carcinogen, both intentional and unintentional exposure remain common. Group-targeted and tailored digital campaigns may help counter protanning norms and strengthen protective behaviors to reduce long-term risk. Objective: This study aimed to evaluate the reach, engagement, and influence of a group-targeted and tailored Instagram-based sun safety campaign implemented as part of a university Skin Smart Campus (SSC) initiative. Methods: A pre-post design was used during the 2024-2025 academic year. The social media campaign evaluation was a focused analysis within a broader sun safety implementation initiative reported elsewhere. The analysis covered the trend-aligned Instagram campaign's reach, engagement, awareness, aided thematic recall, following, and associations with sun safety behaviors. Surveys assessed demographics, sun safety behaviors, campaign awareness, and content recall. Instagram analytics quantified reach and engagement, and influence analyses included bivariate tests and logistic regression. Results: Presurveys and postsurveys were obtained anonymously from 230 and 267 participants, respectively. A dedicated Instagram account and n=10 campus organizations shared campaign content, extending potential reach to 5711 campus followers. Weekly educational posts averaged 262 views and reached approximately 38 nonfollowers per post throughout the campaign. Postcampaign, SSC social media awareness was reported by 48.7% (130/267) of participants, compared to 24.1% (55/230) precampaign (χ²1=32.5; P