By BRET JOHNSON
UNC-CH News Services
CHAPEL HILL -- When asked to explain their conceptions of germs, bacteria and viruses, children participating in a new University of North Carolina at Chapel Hill study relied on television advertisements for toothpaste and household cleaners.
The School of Education study, which compared children's and adults' beliefs about disease, found discrepancies between medical facts and participants' knowledge.
Melissa Rua, an education graduate student, began the project for her dissertation, but found the work to have broad applications.
"These findings are important to science teachers and curriculum developers as well as general practitioners," Rua said. "It's vital to understand what children know before starting to teach. This knowledge could also help physicians communicate more effectively with patients."
Rua will present her work at the American Educational Research Association Annual Meeting today (April 14th) in San Diego.
Study participants included 63 students from central N.C. public schools in the fifth, eighth and 11th grades, four fifth-grade teachers, three middle school teachers and three high school teachers. Teachers came from the same schools as the students.
To compare children's understandings with experts', a virologist, a toxicologist and a medical student also were tested.
The study included concept and association tests, a 30- to 45-minute taped interview and an exercise in which Rua asked participants to draw pictures of germs.
Participants also were asked to identify germ-free areas.
"Medical professionals were reluctant to state a location but eventually said sterilized labs would have fewer germs," Rua said. "A science lab was a common response for teachers and high school students alike."
Other teachers and students said they would expect fewer germs in clean places such as a nurse's office or a hospital, she said. High school teachers thought there were no germs in a vacuum.
"Several students noted areas with extreme weather conditions, such as volcanoes or the arctic, as places where germs couldn't exist," she said. "They also thought there would be fewer germs in areas with less human contact such as deserts, mountains or on the moon."
Throughout testing, the educator found that children frequently referred to the media to support their beliefs.
"Children drew mouths with plaque on the teeth and said they learned that germs grew in the mouth from toothpaste commercials," Rua said. "They also mentioned seeing them in household cleaner ads."
One exercise asked participants to group related words together. Several students grouped "DNA" with "cell."
"Students remembered seeing it used to create dinosaurs in 'Jurassic Park,'" Rua said. "Several students talked about this movie when explaining DNA."
Practical experience also provided students with answers.
"Several elementary students reported that weather was somehow related to getting sick," Rua said. "They gave examples of getting caught in the rain or cold without proper clothing and then becoming sick. When asked to explain what caused the illness, they were unable to answer."
When asked if Tylenol cured germs, more than half of the high school students knew that it soothed pain and was not a cure, a third of middle school children said it soothed pain and most elementary school children believed it decreased germs spreading through the body.
"Few students knew anything about the immune system," she said. "Some students at all grade levels said that white blood cells fight germs, and most thought that the brain told white blood cells when to attack germs."
Middle school children were the only group to report the immune system's location, Rua said. They said it exists -- all over the body, in the stomach or in the lower stomach."
Few students were able to explain how bacteria and viruses differ.
"Adults reported that bacteria are larger than viruses," she said. "But students at all grade levels thought that viruses were larger than bacteria."
The results suggest that educators are doing a good job teaching students how to prevent illness, Rua said.
"However, the research also suggests areas that students and adults are not familiar with. We ought to improve student's knowledge of science and health issues because they are relevant to the experiences they encounter in their daily lives," she said. "Due to the mobile nature of our society, the understanding of microbes and their effects on the body is especially important."
Note: For pictures drawn by students, visit the World Wide Web at: http://www.unc.edu/news/newsserv/pics/rua.html
From April 14-19, Rua can be reached at the San Diego Hyatt Regency at One Market Place (619) 233-1234.
Contact: David Williamson, (919) 962-8596