Recognizing the Importance of Design, Content, and Delivery Features of Health Animations for Preventive Health Behaviors: Realist Review.

Background: Animated messages designed to promote preventive health behaviors (health animations) are a prevalent form of digital health communication globally and are used across a variety of health behaviors. Health animations are visual and can be less reliant on language, helping to reduce health literacy barriers and inequities. Being easily and inexpensively shared, they are a potentially powerful tool for disease prevention. Evidence suggests that animations can be effective in health and non-health care settings. Despite a plethora of health animations in existence and their potential reach and scale, evidence underpinning their design and application, including the potential causal mechanisms at work, is often limited or unknown. Objective: This realist review aimed to understand why, how, for whom, to what extent, and when health animations designed to promote preventive health behaviors work. Methods: The review was conducted in accordance with the Realist and Meta-narrative Evidence Syntheses: Evolving Standards (RAMESES). Peer-reviewed publications identified through database searching from inception until April 27, 2025, as well as gray literature, were considered for inclusion. Animations designed to promote preventive health behaviors in any population and evaluations using any design were included. Animations that could not be viewed, were designed to treat illness or disease, or were part of multicomponent interventions were excluded. Data were appraised for their relevance, rigor, and richness. Data syntheses sought to produce context-mechanism-outcome configurations, contributing to a program theory of health animations. International stakeholder workshops with professionals and members of the public were used to sense check findings and refine the program theory. Results: This review synthesized data from evaluations of 48 health animations. Within the data, design, content, and delivery constructs were identified, including audience or challenge representation, using storytelling, evoking emotion, accessibility, and other contexts. These contexts enabled the triggering of key mechanisms, such as identification, transportation into a story, attention, building self-efficacy, and cognitive processes. The evidence available for synthesis in the building of our program theory of health animations was limited by a lack of data on behavioral outcomes, meaning that the theory is largely derived from evidence of the contexts and mechanisms influencing key determinants known to affect behavior. These key determinants include behavioral intentions, skills and attitudes, and knowledge as a key factor in raising awareness of the need to change behavior. Conclusions: This realist review advances the understanding of the impact of health animations designed to promote preventive health behaviors by providing insight into the design, content, and delivery features at work. Our program theory describes the specific contexts and mechanisms that influence evidence-based determinants of behavior and behavior change. These contexts and mechanisms, therefore, should be considered during health animation design and development processes. A set of 10 recommendations is provided to this end.