Finding ways to encourage the vaccine hesitant to get a shot has led to some creative campaigns. But a pair of studies from the Behavior Change for Good Initiative at the University of Pennsylvania, in collaboration with the Penn Medicine Nudge Unit, shows that the right, simple messaging can be effective as well.
The studies tested the effectiveness of a range of nudges, delivered via text message, to increase vaccination rates of flu shots among two populations: approximately 700,000 Walmart pharmacy patients and approximately 50,000 primary care patients at Penn Medicine and Geisinger.
They showed that simple messaging that reminded individuals a flu shot was “waiting” or “reserved” for them was the most effective, boosting vaccination rates by up to 11 percent.
The purpose of these nudges is to bridge what the researchers call the “intention-action gap” — most people ultimately intend to do what is best for their health, and simple, encouraging messages can help induce that follow-through.
“Rather than convincing the skeptics, we focused on encouraging people who want the vaccine to actually receive it. Our results suggest a promising way to encourage COVID-19 vaccinations at scale. We can potentially help save lives for less than 10 cents per person,” says Katy Milkman, Wharton professor, BCFG co-director, and lead author on both studies.
Such messages can also play on another cognitive bias: telling someone that a shot is “reserved for you” implies that the vaccine already belongs to them and ultimately invokes a sense of loss aversion that motivates action to claim it, the researchers outline. It additionally imposes a sense of reciprocity—the provider has gone to the trouble of setting aside the vaccine dose, and it would be rude not to take it.
Each of these little things can make a big difference in the end.