The Gopher Kids study appears to draw fairgoers back as easily as the Butter Queen or the Big Slide.

Three-fourths of the 530 families (and 850 kids) who were recruited into the study at the 2010 State Fair returned to give follow-up health information at the 2011 fair. The retention rate was closer to 85 percent when adding another 30 or 40 families who didn't make the fair this year but wanted to remain a part of the Gopher Kids project.

"We had a lot of kids who were reminding their parents that they needed to come," said Logan Spector, the lead researcher for Gopher Kids. "They were excited to be participating."

Researchers collected DNA samples via saliva spit kits and basic health information from children and at least their mothers at the 2010 fair.

Spector said many families returned with fathers who weren't at the fair last year to provide their information as well. Eleven families over the past year indicated they no longer wanted to participate -- despite the enticements of free fair tickets -- and wanted their health information and DNA samples destroyed.

Gopher Kids at this point is an experiment on whether the fair could be an effective and low-cost recruiting base. With the success in its second year, Spector plans to apply for a National Institutes of Health grant to recruit thousands of families and to eventually identify how their different genetic and environmental backgrounds influence the health and upbringing of their children.

The study has similarities to the massive National Children's Study, which has been using mass mailings, tents at fairs, and other strategies to recruit expectant mothers from select ZIP codes in Ramsey County and other locations across the country.

The first phase of Gopher Kids recruited families with children ages 1 to 11, but the next phase would likely concentrate on enrolling families with younger children, Spector said. Without NIH funding, the research project is funded by the University of Minnesota only through 2012.

The fair makes the project affordable because it connects researchers and study subjects without having to pay to bring the families to a central research site, Spector said. "That's why we decided to do it at the fair, because we knew people would be there year after year."

Jeremy Olson • 612-673-7744