N C C A M: The National Center for Complementary and Alternative Medicine

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Evaluating Web-Based Health Resources

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Introduction to Evaluating Web-Based Health Resources

The number of Web sites offering health-related resources—including information about complementary and alternative medicineA group of diverse medical and health care systems, practices, and products that are not presently considered to be part of conventional medicine. Complementary medicine is used together with conventional medicine, and alternative medicine is used in place of conventional medicine. (CAM)—grows every day. Many sites are useful, but others may present information that is inaccurate or misleading. When you visit a site for the first time, it’s important to evaluate how reliable it is. This short guide outlines things to consider in your evaluation.


Time to Talk

If you are considering a CAM therapy and find information on the Web, it’s a good idea to share the information with all your health care providers and get their opinions. For tips about talking with your health care providers about CAM, see NCCAM’s Time to Talk campaign at nccam.nih.gov/timetotalk/.


Who Runs the Web-Based Health Resource Site

Any reliable health-related Web site should make it easy for you to learn who is responsible for the site and its information. On the National Institutes of Health (NIH) Web site, for example, each major page clearly identifies NIH and includes a link to the site’s homepage. The National Center for Complementary and Alternative Medicine (NCCAM) Web site follows the same practice; because NCCAM is part of NIH, the NCCAM site’s major pages also link to the NIH homepage.


Who Pays for the Health Web Site

It costs money to run a Web site. The source of a Web site’s funding should be clearly stated or readily apparent. For example, Web addresses (such as NCCAM’s) ending in “.gov” denote a government sponsored site; “.edu” indicates an educational institution, “.org” a noncommercial organization, and “.com” a commercial organization. You should know how the site pays for its existence. Does it sell advertising? Is it sponsored by a drug company? The source of funding can affect what content is presented, how the content is presented, and what the site owners want to accomplish on the site. (For example, if a site about osteoarthritis is funded by a manufacturer of a drug or dietary supplementA product that contains vitamins, minerals, herbs or other botanicals, amino acids, enzymes, and/or other ingredients intended to supplement the diet. The U.S. Food and Drug Administration has special labeling requirements for dietary supplements and treats them as foods, not drugs. that people might use for this condition, that could affect the site’s content.) If the funding source is unclear, or if it is a person or an organization with a proprietary interest in the information presented, try to confirm the information elsewhere (e.g., studies published in scientific journals, or government-sponsored Web sites).


Purpose of the Online Health Resource

The site’s purpose is related to who runs and pays for it. Look for an “About This Site” link on the home page. There you should find a clear statement of purpose, which will help you evaluate the trustworthiness of the information.


Health Information Sources

Many health/medical sites post information collected from other Web sites or sources. If the person or organization in charge of the site did not create the information, the original source should be clearly labeled.


Basis of the Health Information

In addition to identifying who wrote the material you are reading, the site should describe the evidence (such as articles in medical journals) that the material is based on. Also, opinions or advice should be clearly set apart from information that is “evidence-based” (that is, based on research results). For example, if a site discusses health benefits people can expect from treatment, look for references to scientific research that clearly supports what is said. Keep in mind that testimonials, anecdotes, unsupported claims, and opinions are not the same as objective, evidence-based information. Remember: if something sounds too good to be true, it probably is.


How the Health Information Is Selected and Reviewed

If a Web site is presenting medical information, people with credible professional and scientific qualifications should review the material before it is posted. Check for the presence of an editorial board, or other indications of how information is selected and reviewed.


Whether the Health Information Is Current

Web sites should be reviewed and updated on a regular basis. It is particularly important that medical information be current—outdated content can be misleading or even dangerous. The most recent update or review date should be clearly posted. (For example, this information appears at the end of all of the fact sheets posted on NCCAM’s Web site.) Even if the information has not changed, you will see whether the site owners have reviewed it recently to ensure that it is still valid.


Web sites usually have a policy about establishing links to other sites. Some medical sites take a conservative approach and don’t link to any other sites. Some link to any site that asks, or pays, for a link. Others only link to sites that have met certain criteria.


Personal Health Information

Web sites routinely track visitors’ paths to determine what pages are being viewed. A health Web site may ask you to “subscribe” or “become a member.” In some cases, this may be so that it can collect a user fee or select information for you that is relevant to your concerns. In all cases, this will give the site personal information about you.

Any credible site asking for this kind of information should tell you exactly what it will and will not do with it. Many commercial sites sell “aggregate” (collected) data about their users to other companies—information such as what percentage of their users are women older than 40, for example. In some cases, they may collect and reuse information that is “personally identifiable,” such as your ZIP code, gender, and birth date. Be sure to read any privacy policy or similar language on the site, and don’t sign up for anything you don’t fully understand.


Interacting With a Health Information Site

You should always be able to contact the site owner if you run across problems or have questions or feedback. If the site hosts chat rooms or other online discussion areas, it should explain the terms of using this service. Is it moderated? If so, by whom, and why? Spend some time reading the discussion before joining in, to see whether you feel comfortable with the environment.


Additional Resources for Evaluating Web-Based Health Information

This fact sheet was adapted from the National Cancer Institute publication Evaluating Health Information on the Internet.

Other resources include:

For More Information

NCCAM Clearinghouse

The NCCAM Clearinghouse provides information on NCCAM and complementary health approaches, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.

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This publication is not copyrighted and is in the public domain. Duplication is encouraged.

NCCAM has provided this material for your information. It is not intended to substitute for the medical expertise and advice of your primary health care provider. We encourage you to discuss any decisions about treatment or care with your health care provider. The mention of any product, service, or therapy is not an endorsement by NCCAM.

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NCCAM Pub No.: 
Date Created: 
December 2006
Last Updated: 
December 2006