Increased belief in vaccination conspiracy theories predicts increases in vaccination hesitancy and powerlessness: Results from a longitudinal study

Rationale: Vaccinations are an important part of a public health strategy against preventablediseases, and uptake is influenced by factors including hesitancy. The belief of vaccinerelated misinformation including anti-vaccination conspiracy theories has been found to beassociated with increased vaccine hesitancy. Objective: While research suggests that these conspiracy theory beliefs may arise to satisfyunmet needs such as restoring loss of personal control, somewhat ironically these antivaccinationconspiracy theories may frustrate these needs. This study examined the causalrelationships between vaccination hesitancy, vaccination conspiracy theories, and vaccinationrelated powerlessness. Methods: Using a stationary random intercepts cross lagged panel model, we investigated thetemporal ordering of vaccination hesitancy, powerlessness, and vaccination conspiracy theorybeliefs in a sample of Australian adults (N = 500) in a longitudinal study with 5-timepointsover 4-months between June and October 2021. Results: Results from a random intercept cross-lagged model, that separates between-personstability from within-person change, suggested that increased belief in vaccination conspiracytheories was associated with future increases in vaccination hesitancy and powerlessness (butnot vice versa). Findings also showed that increases in vaccination hesitancy and conspiracytheory beliefs predicted respective increases from a person’s trait-level mean at subsequenttimepoints. Conclusions: Vaccination conspiracy theories appear to increase vaccination powerlessnessand hesitancy, rather than satisfying an unmet need for personal control.