Patients look up their illnesses online to become better informed and prepared to play an active role in their care -- not because they mistrust their doctors, a new University of California, Davis, study suggests.

The study surveyed more than 500 people who were members of online support groups and had scheduled appointments with a physician.

"We found that mistrust was not a significant predictor of people going online for health information prior to their visit," said Xinyi Hu, who co-authored the study as part of her master's thesis in communication. "This was somewhat surprising and suggests that doctors need not be defensive when their patients come to their appointments armed with information taken from the Internet."

With faculty co-authors at UC Davis and the University of Southern California, Hu examined how the study subjects made use of support groups, other Internet resources, and offline sources of information, including traditional media and social relations, before their medical appointments.

The study found no evidence that the users of online health information had less trust in their doctors than patients who did not seek information through the Internet.

"The Internet has become a mainstream source of information about health and other issues," Hu noted. "Many people go online to get information when they anticipate a challenge in their life. It makes sense that they would do the same when dealing with a health issue."

Although physician mistrust did not predict reliance on the Internet prior to patients' medical visits, several other factors did. For example, people were more likely to seek information online when their health situation was distressful or when they felt they had some level of personal control over their illness. Online information-seeking was also higher among patients who believed that their medical condition was likely to persist.

The study also found that Internet health information did not replace more traditional sources of information. Instead, patients used the Internet to supplement offline sources, such as friends, health news reports and reference books.

"With the growth of online support groups, physicians need to be aware that many of their patients will be joining and interacting with these groups. These patients tend to be very active health-information seekers, making use of both traditional and new media," the study said.

Almost 70 percent of the study subjects reported they were planning to ask their doctor questions about the information they found, and about 40 percent said they had printed out information to take with them to discuss with their doctors. More than 50 percent of subjects said they intended to make at least one request of their doctor on the basis of Internet information.

"As a practicing physician, these results provide some degree of reassurance," said co-author Richard L. Kravitz, a UC Davis Health System professor of internal medicine and study co-author. "The results mean that patients are not turning to the Internet out of mistrust; more likely, Internet users are curious information seekers who are just trying to learn as much as they can before their visit."

Online support groups provide online virtual meeting places for sharing information and social support. In February 2011, there were more than 12,000 groups listed in the support category of Yahoo! Groups Health and Wellness directory. Even so, other studies suggest that only 9 percent of Americans and 37 percent of patients with chronic disease have participated in online support groups. The majority of subjects assessed their own health as fair or poor.

The study, "The Prepared Patient: Information Seeking of Online Support Group Members Before Their Medical Appointments" was published earlier this year in the Journal of Health Communication.

Co-authors include Robert A. Bell, professor of communication at UC Davis, and Sharon Orrange, assistant professor of medicine at the University of Southern California.