Vaccine Study 4
Messaging in Response to Adverse Events Following Immunization
Impact Canada, Impact & Innovation Unit, Privy Council Office
Summary
Impact Canada’s fourth deep dive study on vaccines. A broadly representative sample of approximately 2,900 Canadians were presented with a hypothetical news report of an adverse event following immunization (AEFI). After reading the news report, participants were randomly assigned to one of seven messaging conditions (including one control and six behaviourally-informed messages) randomly delivered by one of three sources (including the Government of Canada, a top Canadian medical professional, or a spokesperson for the vaccine manufacturer) to assess the impact of the messages and messengers.
Key Insights
Results indicated that behaviourally-informed messages – combining principles such as operational transparency and risk communications strategies – significantly outperformed the status quo communications strategy for responding to AEFI through reducing concerns about vaccine safety and increasing perceptions of message quality. The effect of behaviourally-informed approaches was evident in both contexts of uncertainty (i.e., AEFI is actively under investigation) and certainty (i.e., investigation has concluded). Further, the impact of messaging frames differed depending on the respondent’s ability to identify misinformation about COVID-19 vaccines.