This study is testing different ways of sharing a short, community-informed video about flu and COVID-19 vaccines to see how people respond to it. The video was created with input from Indigenous community members in California and provides information to support vaccine decision-making. Participants may see the video in one of three ways: through a paid advertisement on social media, from a trusted community organization, or from someone they know personally. After watching the video, viewers will be asked to answer one question about how much they trust it, and they may choose to complete a short survey about their vaccine views and how they received the video. The goal is to understand how trust in vaccine information changes depending on who shares it, and to improve the way health messages are delivered to Indigenous and other underserved communities.
This is a randomized dissemination trial evaluating the impact of different message delivery strategies on trust, attitudes, and behavioral intentions related to flu and COVID-19 vaccination. The intervention consists of a short (approximately 2-minute) culturally tailored video, developed using human-centered design and community-based participatory approaches with Indigenous communities in California.
Participants are exposed to the video through one of three dissemination arms: (1) paid advertisements on Facebook and Instagram targeting adults 65 and older in California; (2) peer-to-peer sharing by "seed" participants recruited from a prior phase of the study; and (3) community-based organization (CBO) outreach using established communication channels. All participants view the same video.
After viewing the video, participants are asked to respond to a single poll item ("How much do you trust this video?") and are invited to complete an optional, anonymous online survey assessing vaccine confidence, trust in the information source, and willingness to share the video. Survey responses are linked to the dissemination arm for comparative analysis.
Seed participants receive personalized, trackable video links and instructions to share them with at least 10 contacts in their network. Click-level analytics (e.g., timestamp, referral source, general location) are collected through Bitly or Rebrandly links. YouTube analytics will also be used to evaluate video engagement (e.g., views, retention, traffic source). No identifiable health information is collected unless participants voluntarily provide contact information to complete the survey by phone.
The primary outcome is the level of trust in the video across dissemination arms. Secondary outcomes include survey completion rate, willingness to share the video, and changes in vaccine-related attitudes. Data will be stratified by dissemination method and, for seed participants, linked to prior social network data collected in Phase 1.