Gov. Kate Brown should stop urging Oregonians to get vaccinated against COVID-19 because she is the “least trusted” figure for unvaccinated individuals and could be undercutting the state’s efforts to reach herd immunity, according to new survey results released Tuesday.

In recommendations for how the state could further boost vaccinations, researchers at the University of Oregon’s Institute for Policy Research and Engagement were blunt: “less Gov. Brown.”

“Gov. Brown is a polarizing figure for unvaccinated individuals,” wrote Benjamin Clark and Robert Parker, respectively the co-executive director and the director of strategy and technical solutions at the institute. “We would recommend that (the governor) defer being the primary messenger to unvaccinated Oregonians.”

Brown made Oregon’s COVID-19 response the focal point of her governorship over the last year and she has urged people to get shots in weekly pandemic-focused online media briefings. In May, she announced the state would offer a $1 million lottery and other prizes for vaccinated Oregonians and last week, Brown held a photo op with the winner.

The survey, which included 686 Oregonians and took place from late May through the end of June, found that unvaccinated Oregonians’ own doctors are the most trusted messengers, followed by family and friends. Clark and Parker recommended that state and local government agencies do more to help medical providers do outreach to patients on vaccines, and they also suggested those governments produce guides for the general public on “how to talk to your unvaccinated friends and family about getting vaccinated.”

The governor is a Democrat and the University of Oregon researchers noted that 41% of Republican survey respondents said they were unvaccinated and 48% of nonaffiliated voters who answered the survey said they were unvaccinated. In contrast, only 13% of Democrats who participated in the survey said they were still unvaccinated.

Brown declined through a spokesperson to respond to the findings. The spokesperson, deputy communications director Charles Boyle, indicated the governor will not change her messaging or other work regarding COVID-19 vaccinations.

Five of the researchers’ other recommendations also focused on getting information to a wary or misinformed public, including that vaccines are free and that unvaccinated people make up the bulk of those still getting sick and hospitalized with COVID-19.

They also suggested health agencies apply research on effective messaging when trying to educate the public and enhance those efforts by going to door-to-door – resource-intensive work that they said could be the only option for additional conversions.

But the university’s first recommendation was far less nuanced. Instead of winning hearts and minds with data, the researchers suggested health officials offer $100 cash.

Such an incentive, their research found, could convince one in five of those who say they won’t get vaccinated, and one in three who say they might.

“This is the most accessible and most direct path to Yes for these individuals,” they wrote.

Unvaccinated survey respondents said a $100 bill or cash card would be twice as persuasive as a $1 million lottery to get them to get their shot.

Clark and Parker said the state could better tailor its financial incentives to get the most bang for the buck. They noted Oregon is starting to pay $100 incentives to state workers vaccinated by the end of July, although approximately 80% of public workers in the state are already vaccinated. In contrast, less than 50% of self-employed Oregonians are vaccinated and nearly 70% of employees at family-owned businesses remain unvaccinated, they wrote.