Statistical methods
The difference in proportion of participants intending to receive a COVID-19 vaccine and agreeing with COVID-19 vaccine booster dose belief statements was compared between the control group and each of the four intervention groups using tests of two proportions (z test). A subgroup analysis included data from vaccine hesitant participants only.Previous studies have shown that an effect size of ≥5 percentage points may have practical (clinical) significance [All analyses were conducted using SPSS (Statistical Package for Social Sciences, version 27).