It’s a truth universally acknowledged that people like money. If you show them the cash, they’re generally more likely to do what you want, whether that be to stop smoking, work out, or keep up with their medication.
As vaccines started to roll out of labs during the pandemic, governments began wondering: How can we encourage as many people as possible to get vaccinated against Covid-19? Countries tried a mishmash of approaches: They rolled out rigorous public health messaging, engaged with hard-to-reach communities, got celebrities to plug the vaccines, and made them compulsory.
Those on the utilitarian side say that if more people get vaccinated, the public benefit outweighs all other harms. But there’s no guarantee that offering people money to do a good deed convinces them to do it—it might even suggest the opposite, that the action isn’t worth doing otherwise. A 2000 study conducted with Israeli high school students found that when they were paid a small commission to collect money for charity on a certain day, the group earning a commission actually collected less than the group that was paid zilch—suggesting monetary incentives had a detrimental effect on the urge to do good.
A big worry is that cash incentive programs might have unintended long-term consequences. Offering people money to do a public good deed might reduce their willingness to do the same thing for free in the future. It could also trigger distrust. Unlike blood donation or other public health interventions, vaccines are divisive. And research has shown that in paid clinical trials, people associate higher payments with greater risk. Paying people to get vaccinated—when it’s previously been done for free—might make them overestimate the risks involved.
Finally, the ethics are nebulous. Ethicists argue that a monetary reward does not mean the same thing to a cash-strapped single parent who lost their job during the pandemic as it does to a comfortably employed middle-class person. Offering the money could be seen as a form of coercion or exploitation, as the single parent can’t reasonably decline it. “A gun to the back works, but should we use it?” says Nancy Jecker, a professor at the University of Washington School of Medicine.
But in a new paper published in the journal Nature, researchers Florian Schneider, Pol Campos-Mercade, Armando Meier, and others addressed these concerns.
In 2021, Meier and his colleagues conducted a randomized trial to see if financial incentives increased vaccine uptake. In their study, published in the journal Science in October 2021, Meier and his coauthors recruited over 8,000 people in Sweden and offered a portion of them $24 to get vaccinated within the next 30 days, while the others were offered nothing. The researchers found that the cash incentive boosted the proportion of people who got vaccinated by about 4 percent. That number didn’t change significantly when factoring in age, race, ethnicity, education, or income. Other research during the pandemic also found that financial incentives were effective.