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Information Framing to Increase Flu Vaccination Rates

Information Framing to Increase Flu Vaccination Rates

Project status

Pilot/study with results


Katherine Milkman, PhD 

Penn Behavior Change for Good

Innovation leads


Bill & Melinda Gates Foundation 

Behavior Change for Good 

Penn Center for Precision Medicine

External partners

Geisinger Health System 



The influenza (flu) virus contributes significantly to morbidity and mortality each year. Although the vaccine has been shown to effectively reduce disease and economic burdens, vaccination rates remain low at under 50 percent nationally. 


We conducted two extensive field experiments testing nudges delivered to patients via text message that were designed to boost the adoption of the flu vaccine. Way to Health was used to administer and manage the studies. 

In the first study with Geisinger Health and Penn Medicine, around 50,000 patients with primary care appointments received one of 19 nudges before their visit. In the second study with Walmart, more than 650,000 pharmacy patients received one of 22 different nudges. 


In the Geisinger/Penn Medicine study, the team observed that sending nudges via text message before a primary care visit could boost vaccination rates by an average of 5 percent. Nudges performed best when they matched the typical tone of provider-to-patient communications (i.e., not surprising, casual, or interactive) and notified patients that a shot was “reserved” for them.  

The Walmart study demonstrated that behaviorally informed messages could increase pharmacy vaccination rates by an average of 7 percent over a three-month follow-up period. The most effective nudges matched the tone of typical pharmacy communications and reminded patients that a flu shot was “waiting” for them.  

Health systems and public health organizations can utilize these learnings to optimize campaigns encouraging the adoption of life-saving vaccines. For example, it was exciting to see the New York City officials leverage our research to inform messaging to promote COVID-19 vaccines in the spring of 2021. 

Way to Health Specs

Learn more about the platform
Activity monitoring
Arms and randomization
Criteria-based rules
Dashboard view
Device integration
EHR integration
Multiple languages
Patient portal messaging
Patient-reported outcomes capture
Photo messaging
Remote patient monitoring
Schedule-based rules
Survey administration
Two-way texting
Vitals monitoring