According to the Pew Internet and American Life Project, some 93 million Americans searched for health information online this year, up from 46 million in 2000. But for health communicators, the big numbers mean little without a deeper understanding of how consumers find and use health information.

Enter the Health Information National Trends Survey (HINTS), a biennial survey of Internet behavior launched by NCI in 2003.

"As part of our effort to improve the science of communication, we decided that we really needed to monitor the strategies people use to get cancer information," says Dr. Robert Croyle, director of NCI's Division of Cancer Control and Population Sciences.

From the beginning, Drs. Croyle and Brad Hesse, who leads HINTS, wanted to include as many health communicators in the project as possible. They solicited wide-ranging input before designing the survey and have made all of the HINTS data freely available online. When researchers download data, they register their research protocol. The site lists some 50 ongoing and completed projects and 6 publications based on the 2003 survey.

The latest publication on trust, reliance, and sources of health information, reported in the December 12/26 Archives of Internal Medicine, states that for many adults in the United States, the Internet is the source of first resort for cancer information. Some 64 percent of the nationally representative sample of 6,369 adults say they look for cancer information online, either for themselves or for someone else. Even though older adults search online less frequently than younger adults, 48 percent of those aged 65 and older report researching cancer topics online. And, says Dr. Croyle, "Almost no one goes to libraries anymore."

Yet, Internet information is often considered unreliable. Just 24 percent of respondents say they trust cancer information found on the Internet "a lot." Almost the same proportion say they do not trust such information "at all." Physicians were the most trusted sources, with 62 percent of respondents trusting them "a lot."

"People want to get their information from physicians," says Dr. Croyle, but limited contact means that they tend to turn to the Internet first. As a result, physicians are often confronted with patients waving Web printouts. "Patients want health decisions to be more collaborative, but physicians aren't reimbursed for the time they spend talking through all the printouts," says Dr. Croyle.

Other publications based on the 2003 survey will be forthcoming, says Dr. Croyle, who sees HINTS as a tool to standardize the collection and sharing of data. The HINTS survey itself was designed to complement other large Internet surveys, such as the Pew project. And, says Dr. Croyle, when researchers design local studies, "They can use our survey as a template to make their data most compatible with the national picture."