Vaccine-Preventable Diseases
Conditions
Keywords
herd immunity, community immunity, web-based application, visualization
Brief summary
This study is a PhD project conducted by Ms. Hina Hakim, supervised by Dr. Holly O. Witteman, PhD, and co-supervised Dr. Daniel Reinharz, professors and researchers at the Faculty of Medicine at Laval University. The purpose of this study is to evaluate the effects of visualization conveying the concept of community immunity or herd immunity on risk perception (towards individual, family, community and vulnerable people in communities) (primary outcome) and on emotions, attitudes, knowledge, and behavioural intentions (secondary outcomes).
Detailed description
Visualization is a powerful communication mechanism that uses pre-attentive processing to communicate large amounts of information rapidly in understandable and compelling ways (Healey and Enns 2012). A systematic review demonstrates that there are some interventions available for conveying the concept of community immunity, and very few evaluate interventions for their effects on vaccine intentions and uptake as well as their precursors, such as knowledge, attitudes, knowledge and none on emotions (Hakim et al. 2018). The purpose of this study is to evaluate the effects of visualization conveying the concept of community immunity on risk perception (to individual, family, community and vulnerable people in communities) (primary outcome) and on emotions, attitudes, knowledge, and behavioural intentions (secondary outcomes).
Interventions
BEHAVIORALpublichealthagencycanadaflu
A video showing how herd immunity works in the context of influenza: https://www.canada.ca/fr/sante-publique/services/video/la-grippe-n-en-passez-pas-les-maux.html
BEHAVIORALrobertkochgeneric
A web-based application showing how herd immunity works in general: http://rocs.hu-berlin.de/D3/herd/
BEHAVIORALsbsnewsgeneric
A video showing how herd immunity works in general: https://www.sbs.com.au/news/two-sydney-babies-too-young-to-be-vaccinated-infected-with-measles
BEHAVIORALherdimm
In this visualization participants can build their own avatar representing themselves and 8 other avatars representing people around them, like their family or coworkers. Our visualization then uses these avatars in a brief narrated video explaining how herd immunity works.
BEHAVIORALguardianmeasles
A screen capture of an interactive visualization: https://www.theguardian.com/society/ng-interactive/2015/feb/05/-sp-watch-how-measles-outbreak-spreads-when-kids-get-vaccinated
BEHAVIORALtheotheredmundmeasles
A gif showing measles spreading through populations with differing levels of vaccine coverage: https://imgur.com/gallery/8M7q8#J7LANQ4
Sponsors
Laval University
Study design
Allocation
RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
SINGLE (Investigator)
Masking description
This will be a single-blinded study because we cannot mask participants to the fact that they have been randomized to a visualization e.g., about measles. However, participants will not necessarily know the purpose of the study arm to which they are assigned,and investigators will be blinded to study arm during data analysis (investigators are not aware of whether the next eligible participant will be receiving treatment or control intervention.)
Intervention model description
This study will be a multi-armed factorial randomized controlled trial. Each participant will be randomly allocated to focus on one of four possible vaccine-preventable diseases: measles, pertussis, flu (influenza), or a generic vaccine-preventable disease (hereby referred to as generic). All aspects of the study (visualization, questionnaire) will be focused on that one disease for that participant. The primary and secondary outcomes of the study which are risk perception, emotion, knowledge, trust in information provided, attitudes and a validated scale about vaccination (Betsch et al. 2018) will be assessed in an online questionnaire. Because three online visualizations are available only in English whereas our study will be conducted in both English and French, we will use slightly different randomization patterns for English- and French-speaking participants.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Members of the general population in Canada * At least 18 years old * Able to provide free and informed consent * Able to read and understand French or English * Able to use a computer
Exclusion criteria
\- No internet access
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Risk perception | immediately after intervention or control | 6 items assessing risk perception (item 1 = risk perception as comprehension, scale 0-100, higher numbers better; items 2-5 = risk perception as feelings, scale 1-7, higher numbers better; complete list of items and response wording available in uploaded questionnaire herdimm\_phase3\_questionnaire\_2021-03-01.pdf) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Emotions | immediately after intervention or control | 5 items (e.g., I am worried about getting \[disease\], I would feel guilty if a vulnerable person (a baby, a young child, an older person, a cancer patient) got \[disease\] from me) with a 7-point Likert-type response scale ranging from strongly disagree to strongly agree; higher numbers may be better; complete list of items and response wording available in uploaded questionnaire herdimm\_phase3\_questionnaire\_2021-03-01.pdf |
| Knowledge | immediately after intervention or control | 15 items, with 2 multiple choice questions and 13 true/false questions, for a total possible score ranging from 0 to 18; higher numbers better; complete list of items available in uploaded questionnaire herdimm\_phase3\_questionnaire\_2021-03-01.pdf |
| Trust in information | immediately after intervention or control | Single item (Control: During your life, you may have seen information about vaccines. Thinking about the information you have seen, how trustworthy was it? Treatment: Earlier, you saw a {{video, website}} about herd immunity. Thinking about the {{video, website}} you saw earlier, how trustworthy was the information in it?) with Likert-type response options 1 = not at all trustworthy, 2 = moderately untrustworthy, 3 = slightly untrustworthy, 4 = neutral, 5 = slightly trustworthy, 6 = moderately trustworthy, 7 = strongly trustworthy |
| Vaccination intentions | immediately after intervention or control | Questions conditioned on whether the participant indicates they believe they are already immune to the disease in question, e.g., Imagine you were not already immune to {{measles/pertussis/influenza/a vaccine preventable disease}}. If you were eligible to receive a free vaccine against {{measles/pertussis/influenza/a vaccine-preventable disease}}, how likely would you be to get vaccinated? Response scale on a slider: 0 = extremely unlikely, I would definitely NOT be vaccinated; 100 = extremely likely, I would definitely BE vaccinated; higher numbers better. |
| 5C scale | immediately after intervention or control | 5C scale: 15-item validated scale measuring the psychological antecedents of vaccination (Betsch et al., 2018) |
Countries
Canada
Outcome results
None listed