Skip all navigation and go to page content
NN/LM Home About SCR | Contact SCR | Feedback |Site Map | Help | Bookmark and Share

Fact Sheet
Evaluating Internet Resources

Carolyn Medina
Medical and Research Library, Texas Department of Health, Austin, TX
updated by Shikun ("KK") Jiang, Technology Coordinator, NN/LM SCR, 03/03/2009

The Internet gives users access to millions of pages of information and data from all over the world. However, the Internet is an uncontrolled environment where it is vital for users to be able to critically evaluate the information they see on the Internet in terms of accuracy, quality, and authority.

This fact sheet gives basic criteria for evaluating information specifically on the Internet:


Who wrote this? Authorship is one of the most important criteria used in evaluating information on a website. To be able to assess the information's quality, users need to know the basis of the authority with which the author speaks. Things to look for to establish authority are whether the author lists their own biographical information, whether the author provides contact information and the author's affiliation, whether the author is referenced by another authority, whether the author's web page is linked from another document you trust, and lastly whether the information on the site is accurate and if you can prove its accuracy. Sometimes domain names can also indicate whether a web page is from an authorized source or not. For example, URLs with a .gov domain name are from the United States government, and a URL using .edu as its domain indicate it comes from an educational institution such as a college or a university.


Encountering pages that are several months or even years out of date can be very frustrating for persons doing research on the Internet. Currency refers to the timeliness of information and for most web pages, it is a very important element to determine the information's accuracy and quality.

  • To determine currency of the page itself, look for the date at which the information was last updated (usually located at the bottom of most web pages) or for a copyright date.
  • To determine currency of the information in the page, look for dates when the information was gathered; for example, what is the most recent source listed in the bibliography. If a web page has information that needs to be updated on a regular basis (for example, statistics), the document should include information on the scheduling of updates and be very clear about what time period the statistics refer to.

Verifiability and Accuracy

Currency and authority are elements in determining verifiability and accuracy. Other issues to consider include the research methodology used; the site should describe the evidence that the material is based on. Facts and figures should have references. Also, opinions or advice should be clearly separate from information that is based on research results.


When evaluating the content of a page, further questions to ask are: What is the title of the page and does it do a good job in telling you what the web site is about? Is the page directed toward a specific audience or is it general? Does it match your information needs? Does the page lead you to other sources that are useful? Does the information contradict or support another source either in print or on the Internet?

Another thing to consider is whether the information appears biased or slanted. Note the URL of the document and find out the publishing body. For example, corporations are going to put forth information that presents them in the most positive light, and information on their products may be advertisements. Websites from political people or political parties are bound to be biased! Interest groups may present only one side of a complex issue.


Function refers to the purpose the website is supposed to serve. This criterion helps users better determine whether the information meets their information needs. Questions to ask are: What is the intended purpose of this resource? Does it serve any other purpose (i.e. does it have its own agenda or bias), and who is the intended audience? Is it for academic or popular audiences?

Technical and Visual Aspects (Structure)

More than any other printed format, information on the web requires that the actual structure of the website allows users to be able to easily navigate and locate the information they need. When evaluating a web page, one must consider:

  • How much time does it take for the page to load (very often large unnecessary images or graphics take too long to download)?
  • Is the format standard and readable for most browsers?
  • Are maps and tables readable with most browsers?
  • Is there a text alternative to the images?
  • Do the images, sound or graphics actually supplement the contents of the page or are they distractions?
  • On supporting pages, is there a link back to the main page?
  • Are links still working and are they visible?


Guidelines for Medical and Health Information Sites on the Internet. American Medical Association.

Criteria for Web Site Evaluation. Irwin, K, University of Michigan.

How to Evaluate Health Information on the Internet: Questions and Answers. National Cancer Institute.

Evaluating Internet Sources and Sites: a Tutorial. Purdue University Libraries.