The impact of theory-based messages on COVID-19 vaccination intentions: a structured summary of a study protocol for a randomised controlled trial

Objectives

Uptake of vaccination against COVID-19 is key to controlling the pandemic. However, a significant proportion of people report that they do not intend to have a vaccine, often because of concerns they have about vaccine side effects or safety. This study will assess the impact of theory-based messages on COVID-19 vaccination intention, drawing on the Necessity-Concerns framework to address previously reported beliefs and concerns about COVID-19 vaccination, and assess whether hypothesised variables (illness coherence, perceived necessity and concerns) mediate change in vaccination intention.

Trial design

Prospective, parallel two-arm, individually randomised trial.

Participants

Adults aged over 18 years, living in Scotland and not vaccinated for COVID-19. A quota sampling approach will be used with the aim of achieving a nationally representative sample on gender, region and ethnic group, with oversampling of individuals with no educational qualifications or with only school-level qualifications.

Intervention

Brief exposure to online text and image-based messages addressing necessity beliefs and concerns about COVID-19 vaccination.

Comparator

Brief exposure to online text and image-based messages containing general information about COVID-19 and COVID-19 vaccination.

Primary outcome

Self-reported intention to receive a vaccine for COVID-19 if invited, immediately post-intervention.