The Impact of Theory-based Messaging on Covid-19 Vaccination Intentions

Study Overview
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Brief Summary
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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 its side effects or safety. It is important to identify ways to communicate information about the vaccines that facilitate informed decisions rather than promoting uptake through coercion. This study will assess whether theory-based messages can change beliefs and increase intentions to receive a COVID-19 vaccine in Scotland. The messages will be based on publicly available information about the need for COVID-19 vaccination and the safety of the vaccines, and structured to address specific types of treatment beliefs. Participants will be randomised to either a group shown the messages or a control group shown general information messages about the COVID-19 virus and vaccination programme. By comparing the two groups we aim to test what impact the theory-based messages have on intentions and beliefs about COVID-19 vaccination.

Official Title
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The Impact of Theory-based Messaging on Covid-19 Vaccination Intentions

Conditions
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Vaccination, Covid19

Intervention / Treatment
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* Behavioral: Theory-based messages
* Behavioral: General messages


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Willing and able to give informed consent for participation in the trial Aged 18 years or above Resident in Scotland Exclusion Criteria: Received at least one COVID-19 vaccination dose

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Health Services Research
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Theory-based messages<br>Theory-based health messages about COVID-19 and COVID-19 vaccination, the necessity of COVID-19 vaccination to oneself and others, and COVID-19 vaccine regulatory approval processes. These messages are based on publicly available information and are hypothesised to increase perceived necessity and reduce concerns about vaccination, and target known barriers to vaccine uptake. | Behavioral: Theory-based messages<br>* COVID-19 vaccination information structured to address vaccination necessity and concerns.<br>|
| Active Comparator: General messages<br>General messages about the COVID-19 virus and the vaccination programme. These messages do not target necessity and concerns, but are anticipated to promote understanding of the pandemic. | Behavioral: General messages<br>* General messages about the COVID-19 virus and the vaccination programme.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Covid-19 vaccination intention measured by a single item and aggregated as the proportion of intenders. | Participants will be asked: If you were invited to have a COVID-19 vaccination would you take the vaccine? Those responding yes, probably or yes, definitely will be treated as intenders. Those responding don't know, probably not or definitely not will be treated as non-intenders. | Immediately post-intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean COVID-19 illness coherence score as assessed by the IPQ-R | Self-reported COVID-19 illness coherence as assessed by the the illness coherence subscale of the revised Illness Perception Questionnaire (IPQ-R), with a minimum score of 5, a maximum score of 25 and a higher score representing greater personal understanding of COVID-19. | Immediately post-intervention | 
| Mean perceived necessity score as assessed by the BMQ | Self-reported perceived necessity of a COVID-19 vaccine as assessed by the Specific-Necessity subscale of the Beliefs about Medicines Questionnaire (BMQ), with a minimum score of 5, a maximum score of 25 and a higher score representing greater perceived necessity of a COVID-19 vaccine. | Immediately post-intervention | 
| Mean perceived concerns score as assessed by the BMQ | Self-reported perceived concerns about a COVID-19 vaccine as assessed by the Specific-Concerns subscale of the Beliefs about Medicines Questionnaire (BMQ), with a minimum score of 5, a maximum score of 25 and a higher score representing greater perceived concerns about a COVID-19 vaccine. | Immediately post-intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vaccine hesitancy, vaccination uptake, messaging, illness beliefs, treatment beliefs