Psychological inoculation improves resilience to and reduces willingness to share vaccine misinformation

Vaccine misinformation endangers public health by contributing to reduced vaccine uptake. We developed a 10-minute online game to increase people's resilience to vaccine misinformation. Building on inoculation theory, the Bad Vaxx game exposes people to weakened doses of four different manipulation techniques commonly used in vaccine misinformation (emotional storytelling; pseudoscience/fake expertise; the naturalistic fallacy; and conspiratorial reasoning). Across three preregistered randomized controlled trials (N = 2,326), we find that the game significantly improves participants' ability to discern vaccine misinformation from non-misinformation, increases their confidence in their ability to do so, and improves the quality of their sharing decisions. We also compared two different versions of the game, one where people fight and one where they spread vaccine misinformation. We find that taking the perspective of a character fighting as opposed to spreading misinformation tends to be descriptively more effective, although both versions outperform the control group on most (but not all) outcome measures. Further, we show that participants improve in their ability to correctly identify the use of specific misinformation techniques, but not the truthfulness of the content. Our findings suggest that a short, low-cost, gamified intervention can increase resilience to vaccine misinformation.