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Consumers Home > DES Research > Understanding DES Research > Deciding Whether a Source is Reliable
Deciding Whether a Source is Reliable

Understanding DES Research

 Overview
 Understanding Scientific Research
 Deciding Whether a Source is Reliable
 Role of Laboratory Animal Studies
 Role of DES Cohort Studies

Many sources of information about DES are available. Knowing if the information can be trusted can be difficult. The following are some criteria to help you consider the reliability of a source.

Where was the research published?

Health care providers trust and use research published in credible, peer-reviewed scientific journals. Experts have reviewed studies published in these journals to make sure they are of high quality. Some examples of credible, peer-reviewed journals are JAMA, the Journal of the National Cancer Institute, the New England Journal of Medicine, and Science. If you have any questions about whether a journal is peer-reviewed, ask a librarian or your health care provider.

How does the new information fit with what is already known?

Each research study contributes to an existing body of knowledge. Usually, more weight can be given to study findings that support and build on the findings of other research. If the findings of one study contradict the findings of previous studies, months or several years may pass before more information becomes available to support the contradictory study. In other words, one study alone is never enough to make a case - it simply gives direction about what new research is needed.

How does funding influence research?

Objectivity, the ability to report study results without personal bias, is an important consideration when conducting research. The source of funding for a research project may bias the reporting of results. The funding source is usually included in the journal article. When reading an article from a funded research project, you must consider whether the funders of this research had anything to gain by the results. When research is paid for by a source that does not have an interest in the results, funder's expectations or preferences were less likely to have influenced the results.

Can I trust information from television, magazines, or brochures?

Many health reports in the media are based on articles published in peer-reviewed journals; however, some reports are not. When you see a report on television, in a magazine, or in a brochure, you must consider where this information came from, who provided the information, whether the source is credible, who did the study, and whether it is consistent with other research. If you are unsure, ask your health care provider.

Also remember that news stories focus on what is "new." So when a new study is published in a scientific journal, reporters may highlight the results in their stories as being conclusive. However, a single study is never enough to make a case; new research requires other studies to support the results before a study's findings are considered applicable to medical practice.

I get a lot of my information on the Internet. Is that okay?

More and more, health-related Web sites and newsletters are available to people with Internet access. This Web site is an important part of CDC's DES Update and includes sections for health care providers and the public. Use the preceding guidelines to think about the credibility, expertise, bias, and funding of the source of information. The most credible Internet sites come from recognized experts, like health agencies and reputable health and medical organizations. If you are unsure, ask your health care provider for credible Web sites.

CDC's DES Update also provides a list of credible health information sources.

I've heard lots of stories about DES exposure that aren't in the research. Why is that?

Personal stories, sometimes called "anecdotal evidence," refer to individual experiences. They may or may not be consistent with scientific research. An important element of studying large populations (like the DES cohort studies) is that individual experience is included in the reported data. Even though you may have heard details from persons that are not consistent with findings from scientific research, those experiences have been averaged into the population data. Scientific evidence from large studies (like the DES cohort studies) is reliable, because the studies are rigorous and better reflect the experiences of the population that is being studied.

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