Applying the Multiphase Optimization Strategy to Develop and Test a Culturally-Relevant Digital Health Intervention Targeting HPV Vaccination among U.S. Vietnamese - PROJECT SUMMARY/ABSTRACT U.S. Vietnamese individuals (i.e., those living in the U.S. and identifying as Vietnamese) experience high rates of HPV-related cancers. Despite the benefits of HPV vaccination to prevent HPV-related cancers, U.S. Vietnamese adolescents have low HPV vaccine uptake (52% initiation and 35% completion). Digital health can potentially be an effective approach to deliver culturally-relevant interventions targeting HPV vaccination among U.S. Vietnamese, especially given the high rates of internet use in this population. Yet, few digital health interventions on HPV vaccination exist for U.S. Vietnamese. More critically, existing digital health research on HPV vaccination for Asian Americans and/or U.S. Vietnamese have typically employed the classic “treatment package” approach where different intervention components are bundled into one package and the entire package is tested in a trial. This approach fails to identify either the individual effect of each component or whether the effect of one component is changed by the presence of other components. Understanding distinct impacts of intervention components is critical for ensuring intervention efficiency, affordability, scalability, and effectiveness. This study, HPV Education & Resources for the U.S. Vietnamese Population (HERO), will address this critical gap. Dr. Ha Ngan (Milkie) Vu will leverage the Multiphase Optimization Strategy (MOST) framework to conduct a pilot trial testing four different intervention components (expert video, self-persuasion, narrative storytelling, and motivational interviewing) targeting HPV vaccination among U.S. Vietnamese. Additionally, she will apply an implementation science framework to explore factors influencing the future implementation of the intervention., represents the first systematic effort to assemble an optimal digital HPV vaccine intervention for U.S. Vietnamese. The specific aims are to: (1): Assess the feasibility and acceptability of each of the four digital HERO intervention components in a pilot trial; (2) Investigate effects of each component on HPV vaccination outcomes and psychosocial mediators; and (3) Explore factors that may influence the future implementation of HERO. This research is responsive to NCI’s priorities, including health equity, digital health, and reducing cancer health disparities as well as to NIH’s efforts to enhance research on Asian Americans’ health. The proposed K01 research activities build on Dr. Vu’s formative research and are supported by robust community and clinic partnerships. They also align with her career development plan, which includes training in (1) clinical trials design, conduct, and evaluation; (2) digital health; (3) implementation science; and (4) professional development. Dr. Vu has assembled a strong team of NIH-funded mentors and advisors with extensive experience in mentoring junior investigators to independence. The K01 will be foundational to Dr. Vu’s career goal of becoming a leading independent researcher who develops, implements, and tests culturally-relevant, evidence-based digital health interventions to reduce cancer health disparities experienced by Asian Americans and underserved populations.