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Sources of trustworthy information about treatment effects

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Where should you look for trustworthy information about the effects of treatments for health problems?

Where should you look for trustworthy information about the effects of treatments for health problems?

Because this website does not provide information about the effects of specific treatments for health problems we have identified three of the best sources of this type of information.

To find out why, read on.

What kind of information should you be looking for?

  1. You need to be able to understand the information, so it should be written in plain language.
  2. You need to be able to judge whether the information is likely to be trustworthy.
    Ideally, you’d want:

    1. the information to have taken account of ALL the research evidence relevant to your question ;
    2. the evidence to have been reviewed systematically, and to be readily accessible
  3. You may also want to know about relevant ongoing studies, because you may want to find out about or participate in one or more of these.

So, which information sources do we recommend you consider?

We considered 29 English language websites that provide evidence-based information about the effects of treatments. Three of these – Cochrane Evidence, Informed Health, and PubMedHealth – are intended for patients and the public, and provide information in plain language based explicitly on systematic reviews. A full report of how we selected these three websites and our findings can be found here.

Tips for using these websites

The appeal of each of the three selected websites may vary depending on the questions being asked and the individuals posing them. All three websites provide plain language summaries of systematic reviews, have glossaries, and indicate how up-to-date the information is. However, information about treatment effects is not reported consistently on any of the websites. PubMed Health is the least consistent and Informed Health the most consistent. We found PubMed Health somewhat easier to search than the other two websites.

Searching the three websites frequently yields much irrelevant information. You can limit searches by using “Boolean logic”. If you retrieve a lot of irrelevant information, try inserting AND between terms (e.g. for the condition AND for the treatment) and USE quotation marks to indicate that words need to be next to each other (e.g. “back pain”).

If you are unable to find trustworthy information about treatment effects on the three websites we have selected, you can try searching Epistemonikos, a free-access database that contains scientific summaries for over 100,000 systematic reviews (not all of treatment effects). These summaries are translated to Arabic, Chinese, Dutch, French, German, Italian, Portuguese, and Spanish. Epistemonikos is not intended for patients and the public, and plain language summaries are not available for most of the reviews. However, it is easy to search and some people may find the scientific summaries helpful.

None of the three websites listed below include links to ongoing studies. If there is important uncertainty about the effects of relevant treatments, you might want to consider searching for ongoing trials using the World Health Organization International Clinical Trials Registry Platform Search Portal, NHS Choices, or a clinical trials registry.


Cochrane logoCochrane Evidence

Cochrane Evidence provides plain language summaries of information about treatment effects from over 7000 Cochrane Reviews. The summaries are translated into Chinese, Croatian, Czech, French, German, Japanese, Korean, Malay, Polish, Portuguese, Romanian, Russian, Spanish, Tamil, and Thai.

Cochrane Reviews are systematic reviews of the effects of treatments. The systematic reviews and the plain language summaries are prepared and updated by Cochrane review groups. Cochrane is a global, independent network of researchers, professionals, patients, carers, and people interested in health, with over 37,000 contributors from more than 130 countries


Informed Health OnlineInformed Health

Informed Health provides information about treatment effects and other helpful information on a wide range of topics. The website includes “research summaries” only for some treatments. In addition to information about treatments, Informed Health includes information about symptoms, causes, outlook, diagnosis, everyday life, where to learn more, and explanations (“Extras”) of topics such as how the body works, how treatments work, and types of treatments.

Informed Health is the English-language version of the German website Gesundheitsinformation.de. The website is prepared by the Institute for Quality and Efficiency in Health Care (IQWiG) in Germany. IQWiG is a professionally-independent, scientific institute established under the 2004 Health Care Reform.


PubMed Health logoPubMed Health

PubMed Health includes a large number of systematic reviews of treatment effects, and plain language summaries for Cochrane Reviews and some other reviews. It has an extensive glossary.

PubMed Health is a service provided by the National Center for Biotechnology Information at the U.S. National Library of Medicine. It includes information based on over 40,000 systematic reviews from a variety of sources, but plain language summaries are not available for most of these.