When Todd Bunce was asked Thursday to complete a University of Minnesota survey on how physician dress affects patient attitudes, his question wasn't so much why, but, eh, why not?

Because when you go to the Minnesota State Fair, you try random things — whether eating dill pickle tots or observing the new cat-and-dog exhibit or, in this case, volunteering to aid science. After 10 years, the organizers of the university's Driven to Discover Building have discovered that they can count on that spirit from people like Bunce, who have participated in more than 100 published scientific papers and more than 30 student dissertations or projects.

"Some of it is, 'I want the backpack,'" which is given away as a recruitment incentive, said Ellen Demerath, a co-director of the so-called D2D building and a public health researcher. "Some of it is, 'I want to understand what they are doing,' and I love that. Folks who come to this fair are curious; they expect to see new things."

More than 440,000 people in the past decade have visited D2D, a gold-and-maroon pavilion near the 4-H Building, and more than 150,000 have signed up for studies. Researchers this year are collecting bacterial samples from fairgoers to understand what causes cavities, monitoring children's brains while they play video games and assessing public comfort with the explosion of recreational cannabis products.

Perhaps the most telling sign of success is that researchers pay for the access. A U grant had made it free to set up a study booth in the early years, but when that money ran out, researchers were eager to rent the space so they could continue to tap into the fair's huge crowds, said Logan Spector, a D2D co-director and pediatrics researcher.

"It has grown into exactly what we were hoping for," he said.

D2D pays for itself, gaining revenue from researchers at the U and other colleges as well as biotech firms. Boston Scientific and Biomedix teamed up on a test this year that measures differing blood flow rates in volunteers' fingers and toes and assesses them for blocked blood vessels.

Dr. Meredith Adams and her U colleagues keep coming back every year to study ear health. In prior years, they have tested whether Q-tips actually clean out volunteers' ears and have collected ear wax samples to see what types of bacteria grow in the ear canal. This year, they were checking the hearing of volunteers and finding out the barriers that have prevented those with hearing loss from seeking care.

"I mean, this is reaching people who have regular, everyday problems," Adams said. "That is who we need to hear from."

Spector launched the Gopher Kids study at the main U building at the fairgrounds in 2010, collecting saliva samples and data from families to study genetic and environmental origins of child health. Participants were waiting for the doors to roll open on day one, he recalled.

Thousands of people visited even when D2D first set up in the old Spam building, a dilapidated structure with a cattle chute that dumped water on the floor when it rained, he said. "Whatever magic we had," Spector said, "it was enough to overpower the awful environment."

The D2D building lives by two rules. It hosts only studies that present minimal risks, a requirement of a U ethics panel, and it rarely asks visitors to spend more than 20 minutes on any task.

As a result, many studies are based on quick surveys of public perception or human behavior, or on lab samples such as saliva and ear wax that can be collected rapidly. U pediatricians turned responses from fairgoers in 2021 into a paper last year on the most effective means for doctors to communicate with patients. Hamline business researchers analyzed what makes people susceptible to fraud and pyramid schemes.

Bunce brought a chilled coffee into the U building, where he signed up for the federal All of Us research program that is collecting genetic and health information from 1 million Americans. Then he took part in the Power of Perception survey about whether patients have more confidence in doctors and nurses who dress up. Like many fairgoers stopping by on Thursday morning, he had one motivation.

"Backpacks," the St. Paul man said. "You gotta get the backpacks, every year."

A third, unwritten rule of D2D is that studies need snappy titles. Ten research groups can be operating at once, leaving them to compete for participants.

Brianna Kreft had participated in studies at the fair as a child. Now a political science graduate student, she was excited to survey visitors this summer for her own project — "Who Likes Politics Anyway? The Rural-Urban Divide in Political Attitudes."

"What's funny is, a lot of people will see the sign ... and audibly go, 'Oh, you don't want to hear what I have to say. I don't like politics,'" she said. "And I say, 'You're actually exactly who I want to hear from!'"

The attraction has proved so successful that leaders of other state fairs are considering copying it. Demerath, the co-director, said D2D expanded over the past two years, using grant funding to offer a few research opportunities at county fairs and recruit rural Minnesotans who don't come to the Twin Cities.

Buffalo seventh-grader Brynn Torkelson came straight to the U research building with her mother on Thursday morning, as part of their annual dawn-to-dark visit to the fair. She enjoyed a study last year of virtual reality technology and how families adapt to it.

"I always like learning more and [volunteering] helps other people learn," Brynn said.

"And the free stuff is a bonus," her mother, Brooke Torkelson, said.


Correction: An earlier version of this article misspelled Biomedix, an Eagan diagnostics company.