Electronic Nudges for Influenza Vaccination

To the Editor In a recent study, electronically delivered nudges directed at patients with chronic diseases significantly improved influenza vaccination uptake, although the magnitude of improvement was limited. This result may have reflected the selection characteristics of the study population, which included patients with chronic diseases who likely had high baseline awareness of the benefits of influenza vaccination. Consequently, high baseline intent may have attenuated the intervention’s effect. The “repeated letter” group achieved the greatest increase, improving by 13.5%, while other messaging frames, such as “cardiovascular benefits” and “respiratory benefits,” yielded gains of approximately 11.0% to 11.9%. These increases were modest relative to the control group, suggesting a ceiling effect in populations with preexisting intent to be vaccinated.