Influence of age and message frame on COVID-19 vaccination willingness early in the pandemic

Objective: This study examined whether age would moderate the association between a brief message frame intervention and COVID-19 vaccine willingness. Methods: Data were collected in Australia between 25 June and 5 July 2021. Participants (N = 187) aged 18-85 years had not yet received a dose of COVID-19 vaccine. After random assignment to a gain- or loss-framed message, participants reported COVID-19 vaccine willingness, general anti-vaccine attitudes, approach and avoidance motivation, and COVID-19 illness risk perception. Results: Message frame did not influence COVID-19 vaccine willingness. However, greater COVID-19 illness risk perception and older age increased the odds of Pfizer vaccine willingness, while lower avoidance motivation increased the odds of AstraZeneca vaccine willingness. Greater anti-vaccine ideology decreased the odds of willingness to receive either of the COVID-19 vaccines. Conclusions: A brief message frame intervention did not influence COVID-19 vaccine willingness across the adult lifespan.