Grant: Catalyst Grant: SPOR Innovative Clinical Trials (iCT)

Recent research by our team provides substantial evidence that influenza vaccination is an effective public health strategy for the prevention of stroke in adults as well as the prevention of influenza. Influenza vaccine in Alberta is around 28%, consistently below the national average of 40%. This indicates an urgent need to increase vaccination rates. Behavioural nudges have been shown to be effective tools that increase influenza vaccine uptake in several jurisdictions. Nudges, a concept from behavioural economics, are adaptations to the context in which a decision is made to influence the behaviour of groups or individuals. We seek to determine which type of nudge is most effective in increasing influenza vaccine uptake in Alberta. We will use focus groups and a survey with people with lived experience of influenza and stroke to develop messages. We will recruit 5190 participants aged 40 and above through Alberta Health Insurance Plan registry data and use a 2x2 factorial design individual-level pragmatic randomized policy trial to compare outcomes among four groups: (1) control (no letter), (2) letter with an influenza risk reduction message, (3) letter with a cardiovascular benefit message, (4) both a letter with an influenza risk reduction message and a letter with a cardiovascular benefit message. We anticipate a 5% increase in uptake of influenza vaccination which, if implemented province-wide, would lead to a decrease of approximately 60 stroke event in the 6 months following influenza vaccination, avoiding $3,000,000 in health care costs.