Exploring Changes in COVID-19 Vaccination Intentions by Prompting Altruistic Motives Using a Video Intervention
Condition: Vaccine Refusal
MeSH terms: COVID-19
Study type: Interventional

Summary: 
      As Canada records over 1,400,000 COVID-19 infections and 26,000 deaths, the need to stop the
      spread of the virus has become increasingly critical. Although younger individuals (aged
      20-39) have lower hospitalisation and death rates than older adults, they have high rates of
      infection and may be less willing to accept a vaccine because they consider the disease to be
      less dangerous for themselves. It is of concern that around 30% of Canadians, especially
      younger adults, will not be willing to accept a COVID-19 vaccine. Vaccination will be the
      best method to control the pandemic in the future and protect those at higher risk of
      hospitalisation and death (e.g., elderly, those with chronic diseases). Therefore, achieving
      high rates of vaccination coverage among younger adults is very important in the long run to
      protect not only themselves but also others. For the experimental condition, the
      investigators will develop a brief video that will promote the vaccine's protection of others
      (altruism). For the control condition, the investigators will create an informational text on
      COVID-19 preventative health measures based on recommendations from the Public Health Agency
      of Canada. 2630 younger adults (aged 20 to 39) who have not yet received a dose of a COVID-19
      vaccine will be recruited. To match Canadian demographics, participants will be recruited
      using the following quotas to reflect census data from Statistics Canada: 50% male and 50%
      female; 80% Anglophone and 20% Francophone; 80% urban and 20% rural; and 50% household income
      level less than $75,000 and 50% household income greater than $75,000. Half of the
      participants will be randomly assigned to watch the video, with the other half reading the
      text. In both groups, participants will complete a short online survey before and after
      viewing the video or reading the text. The goal is to assess the efficacy of the video on
      increasing younger adults' willingness to get a COVID-19 vaccine. The research team is
      partnering in this study with key agencies, e.g., Public Health Agency of Canada (PHAC),
      National Advisory Committee on Immunization (NACI), and the Institut National de Santé
      Publique du Québec (INSPQ) to help communicate the research findings to the general
      population.
    

Detailed description: 
      The COVID-19 vaccine is the most effective way to arrest the pandemic. A high vaccine
      acceptance rate is needed to achieve community immunity; however, current COVID-19 vaccine
      acceptance rate remains low, particularly among younger Canadians. There have been no studies
      that have examined the impact of altruism on COVID-19 vaccine intentions using a video-based
      intervention. The investigators will examine the efficacy of a video intervention eliciting
      altruism on increasing younger Canadians' (ages 20-39) intentions to receive the COVID-19
      vaccine using a randomized control trial. The results of this study will be used by public
      health authorities to increase COVID-19 vaccine uptake. There are two objectives of the
      study: 1) to assess the within-participant efficacy of the video intervention in increasing
      vaccine intentions; 2) to assess the between-participant efficacy of the video intervention
      in increasing vaccine intentions.

      A 10-minute survey will be administered online to a sample of 2630 Canadian residents aged
      20-39 years old and is available in both English and French. To calculate the required sample
      size for the within-participant change in vaccine hesitancy (i.e., pre-post video
      intervention) the investigators used survey data showing that approximately 40% of Canadians
      in this age group are COVID-19 vaccine hesitant i.e., don't know yet or would refuse
      vaccination. Estimating a 5% decrease of hesitancy in the video intervention group and a
      correlation of about 0.45 between paired observations, this group requires a sample size of
      1315 pairs for detecting a 5% change of marginal proportions at a power of 80% and two-sided
      significance of 5%.

      Participants will be randomized using a one-to-one ratio. Thus, 50% will be allocated to the
      video intervention and 50% to the text intervention. Using equal size groups will allow for
      the detection of a between group difference in vaccine intentions of 5-6% with a power of 0.8
      and a two-sided significance of 5%. The total sample required for this study is 2630
      participants i.e., 1315 in the video intervention group and 1315 in the text intervention
      group.

      The investigators have contracted Dynata, the world's largest first-party data and insight
      platform, to conduct recruitment and host the survey. Dynata will send invitations in various
      forms (e.g., e-mail invitations, text messages and in-app alerts) to recruit eligible
      participants from their existing panel (individuals who have signed with Dynata and have
      expressed willingness to receive invitations to various appropriate surveys) until
      recruitment goals and quotas are met.

      Stratified randomization will be used to allocate participants to either: 1) video
      intervention: viewing a 2-minute altruism-eliciting video, or 2) text intervention: reading a
      text containing information from the Public Health Agency of Canada about general health
      behaviours and public health recommendations concerning COVID-19, e.g., hand hygiene and
      respiratory etiquette, wearing non-medical masks, physical distancing, etc. Within each
      stratum (first language, sex, population density and household income), participants will be
      allocated randomly using a one-to-one ratio (one to the video intervention and one to the
      text intervention).

      Participants will first be asked to answer several socio-demographic questions and will be
      asked to choose one of the following categories which describe their COVID-19 vaccine
      decision-making stage according to the Precaution Adoption Process Model (PAPM): unengaged,
      undecided, decided not to receive the vaccine, or decided to receive the vaccine.
      Subsequently, depending on their randomly assigned condition, participants will either be
      shown a 2-minute altruism-eliciting video, or a brief informational text. After viewing this
      content, to ensure that participants paid attention, participants will answer questions about
      the contents to check their understanding. Finally, participants will: 1) once again be asked
      to choose their COVID-19 vaccine decision-making stage; 2) be asked questions regarding
      previous vaccination history (e.g., seasonal influenza), lifestyle factors, self-perceived
      health status, personal history of SARS-CoV-2 infection, and preferred health-information
      channels; and 3) complete validated scales regarding altruism, empathy, personal distress,
      and vaccine hesitancy.

      To test the outcome for objective 1, the McNemar's test will be used to compare paired
      (pre-post video intervention) proportions. To control for the potential effect of other
      factors (e.g., sociodemographics, previous influenza vaccination, lifestyle factors), the
      investigators will conduct multivariate analyses (General Estimating Equations) and estimate
      the associations between these factors and changes in COVID-19 vaccine intentions. For
      objective 2, the difference in proportions between the video intervention and text
      intervention will be analyzed using the Chi-square test. The investigators will test for
      significant differences in predictor variables between the two groups and use logistic
      regression analyses to estimate the associations between these variables and the outcome
      (vaccine acceptability). The significance level will be set at α = 0.05.
    

Intervention name(s): Altruism Video; COVID-19 Informational Text
Intervention type(s): Behavioral; Behavioral
Intervention description(s): The video provides three vignettes about a diverse set of people who may be more vulnerable to serious health consequences from COVID-19. In each of the stories, high vaccine uptake of those around these vulnerable individuals serves to protect them. This communicates that getting the COVID-19 vaccine can be done for prosocial reasons and to foster a sense of community, as it provides protection not only to oneself, but also to others.; The topics included in the text are how COVID-19 spreads, hygiene, physical distancing, and travel restrictions. Participants will complete three comprehension questions, one after each of the following sections: hygiene, physical distancing, and travel restrictions.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Participants will be assigned to either the video intervention or informational text control condition using a 1:1 randomization ratio.
Masking: Single (Investigator)
Primary purpose: Prevention
Keywords: Vaccine Hesitancy; Vaccine Decision Making; COVID-19