U.S. surveys in recent years have calculated atheists make up between 3 percent and 10 percent of the population.

But the percentage may actually be much higher, because the stigma surrounding disbelief in God likely prevents people from honestly answering pollsters’ questions about their beliefs, according to a new report by University of Kentucky psychologists Will Gervais and Maxine Najle.

“There’s a lot of atheists in the closet,” Gervais said in a recent interview with Vox.

Gervais and Najle’s report, to be published in the next issue of the journal Social Psychological and Personality Science, concluded the true number of American atheists may be as high as 26 percent of the population.

There’s a lot of atheists in the closet."

This stands in stark contrast to surveys conducted by Pew Research Center and Gallup — highly reputable polling operations. A 2014 Pew survey found the percentage of Americans who said they were atheists to be just over 3 percent, with 9 percent of adults reporting they didn’t believe in God, which is the definition of atheism.

A 2016 Gallup poll found that 10 percent of Americans reported they did not believe in God.

Gervais isn’t buying that data.

“We shouldn’t expect people to give a stranger over the phone an honest answer to that question,” Gervais told Vox.

The University of Kentucky study aimed for a more accurate analysis using what’s called “the unmatched count technique.” Gervais and Najle sent a poll to two nationally representative samples of 2,000 adults. Instead of asking respondents directly about their belief in God, the researchers asked participants to read through a list of statements, including things like, “I own a dog,” and “I enjoy modern art.” One group of respondents had the statement, “I believe in God,” included on their list.

The participants were asked to write down the number of statements that were true for them. Gervais and Najle operated on the assumption that the two groups should have roughly the same number of dog owners, art lovers, et cetera. Any major differences would account for those who don’t believe in God.

There are profound social pressures to be -- or at least appear -- religious."

Gregory Smith, associate director of research at Pew Research Center, was skeptical of the new report. “I would be very reluctant to conclude that phone surveys like ours are underestimating the share the public who are atheists to that kind of magnitude,” Smith told Vox.

But there is social stigma surrounding atheism in the U.S., which Gervais argued may lead people to tell pollsters they believe in God even if they don’t. A January 2017 Pew survey asked respondents to rate different groups on a “feeling thermometer” ranging from 0 to 100. On average, atheists received a rating of 50, which was lower than all but one religious group ― Muslims.

An analysis of data from the 2014 Boundaries in the American Mosaic Survey found that 42 percent of U.S. adults say atheists don’t share their vision of American society.

“Given the centrality of religious belief to many societies, and the degree to which many equate religious belief with morality, there are profound social pressures to be ― or at least appear ― religious,” Gervais and Najle wrote in the report.