Digital nudges boost flu vaccine uptake in High-Risk adults
NCT ID NCT06600490
First seen Jun 25, 2026 · Last updated Jun 26, 2026 · Updated 1 time
Summary
This completed study tested whether sending behavioral nudges through Denmark's official electronic letter system could increase flu vaccination among adults aged 18-64 with chronic diseases. Over 300,000 participants were randomly assigned to receive different types of letters or no letter. The goal was to see if simple, well-designed messages could encourage more people to get vaccinated, potentially reducing flu-related complications in this vulnerable group.
What this could mean
Our plain-language read of the trial. This is informational only — not medical advice or a prediction.
Active substance
behavioral nudges (letters using behavioral economic principles)
What this could lead to
If effective, this approach could provide a low-cost, scalable way to boost flu vaccination rates in high-risk populations, reducing flu-related illness and hospitalizations.
What could go wrong
This is a completed trial confirming previous findings; results may not generalize to other countries or populations. The intervention is a nudge, not a vaccine, so its impact depends on individual behavior.
Disclaimer
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This is a summary of
the original study
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Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.
This is a summary of the original study . Summaries may miss details or leave out important information. Before applying or accepting participation, make sure you have read and understood the full study. Curemydisease.com takes no responsibility whatsoever for anything missed, misunderstood, or acted upon as a result of our summary — we know it does not capture everything.
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Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
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Locations
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Center for Translational Cardiology and Pragmatic Randomized Trials, Department of Cardiology, Copenhagen University Hospital - Herlev and Gentofte
Hellerup, Capital Region, 2900, Denmark