Discussion
fatigue
WEDDINGS, INFLUENZA
This experiment found some evidence that messages emphasising non-health benefits of getting a COVID-19 booster dose, like travelling, enjoying family occasions like weddings, and seeing family and friends, may increase intention to vaccinate, especially in hesitant populations. In this study, intention was qualitatively higher in participants who viewed messages about non-health benefits compared to those who viewed messages about health benefits for themselves and the community. This is somewhat consistent with findings from an experiment in US adults [This study also found some evidence that messages emphasising benefits of COVID-19 vaccine booster doses to people’s personal health and the health of the community may increase intention to vaccinate. These findings are consistent with a systematic review of COVID-19 vaccine interventions [This study found that messages emphasising personal agency may have negative impacts, especially with hesitant individuals. This finding contrasts with previous findings, which suggest that individual liberty and a sense of personal agency when choosing vaccination may motivate people to vaccinate [Finally, in terms of COVID-19 vaccine booster dose beliefs, this study found more increased changes in beliefs in hesitant participants compared to the whole study population. This suggests that hesitant participants have beliefs that are possibly less fixed and more amenable to change, a result that has been found in studies about childhood vaccination [These have practical implications for communications from health authorities and other stakeholders to encourage uptake of COVID-19 booster doses, especially communications directed at individuals consuming vaccination information online. Health authorities should consider using a range of messages; an emphasis on non-health benefits may be particularly useful, although personal and community health benefits may also be effective. Any message should be pre-tested with target audiences; message effectiveness will depend on current circumstances and sentiment. Interventions specifically designed for and targeting hesitant, undecided populations are likely to bear the most fruit. For this population, messages emphasising personal agency should be used with caution. Until more evidence emerges, caution should also be taken with messages that leverage prescriptive norms that tell people how they ought to act (i.e., what the ‘right’ vaccination behaviour is). In all instances, messages should be tailored for specific communities, taking into account differences in factors affecting motivation to vaccinate and health literacy. Caution should be used when extrapolating this evidence for use with messages directed at individuals hesitant about other vaccines. Research with the community during the initial rollout of COVID-19 vaccines indicates the vaccines are perceived to be considerably different from other vaccines give their use of novel technologies (such as mRNA) and rapid development. Some individuals who report being accepting of most vaccines have indicated hesitancy in relation to COVID-19 vaccines [Future research could use qualitative methodologies to explore message development and testing to better understand the negative effects observed in this study. Research to better understand the effect of messages that leverage prescriptive norms would be useful. Exploring the effects of messaging on different age groups, as well as messaging that caters for varying literacy levels, would provide evidence to support development of more nuanced and targeted communications. Likewise, developing and testing different message formats beyond written information, such as videos and infographics, and channels beyond a static webpage would also be useful. Research focusing specifically on at-risk groups and hesitant populations would ensure greater vaccine equity and would provide useful insights into intervention effectiveness in key target populations. At-risk groups could include the elderly, pregnant women and people, people from different cultural or Indigenous communities, and people with disabilities. Several years into the COVID-19 pandemic, it would also be useful to understand ‘vaccine information fatigue’ (i.e., the extent to which communities have switched off from and appear immune to communication about COVID-19 vaccines), and how to continue encouraging uptake. This is particularly important if health authorities are to consider additional booster doses or an annual COVID-19 vaccine. Furthermore, given the overall high intentions found among the sample in this study, future research may need to shift the focus to interventions that translate intention into vaccination behaviour (i.e., people getting vaccinated). This could involve the use of behavioural nudges, such as text message reminders, which has shown some positive results early in the COVID-19 vaccination rollout, as well as with other vaccines such as influenza [This study has limitations. In this study, participants only saw the message once from a single source; multiple exposures from multiple sources over time may be required for long term changes to intention and behaviour to occur. This study did not measure changes in behaviour, but rather measured vaccination intention as an outcome. While in keeping with similar studies, behaviour in the form of vaccination uptake would provide a more accurate measure of the effectiveness of such interventions. Some of the intervention texts had a slight overlap. There was a clear emphasis on a single area of focus in each text via a bolded title and repetition of the particular benefit throughout the text. Future research, however, should use a manipulation check to verify that participants can identify the condition they are in, as well as checks to assess comprehension. The sample was highly educated, likely a result of the nature of the panel used. Online research panels in general are likely to represent people who are digitally literate and are willing and able to spend time responding to email invitations and surveys [