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Home >> Research & Instruction >> Research Help >> Evaluating information

Why Evaluate?

Once you have found information that matches the topic and requirements of your research, you should analyze or evaluate these information sources. Evaluating information encourages you to think critically about the reliability, validity, accuracy, authority, timeliness, point of view or bias of information sources.

Just because a book, article, or website matches your search criteria and thus seems, at face value, to be relevant to your research, does not mean that it is necessarily a reliable source of information.

It is important to remember that sources of information comprising the Library's print and electronic collections have already been evaluated for inclusion among the Llbrary's resources. However, this does not necessarily mean that these sources are relevant to your research

This does not necessarily apply to sources of information on the Web for the general public. Many of us with Internet/Web accounts are potential publishers of websites; most of this content is published without editorial review. Think about it. Many resources are available to help with evaluating web pages.

Questions to Ask

What criteria should you use to judge information sources?

Initially, look at the author, title, publisher, and date of publication. This information can be found in the bibliographic citation and can be determined even before you have the physical item in hand.

Next, look at the content, e.g. intended audience, objectiveness of the writing, coverage, writing style, and, if available, evaluative reviews.

The following questions should be asked:

Who is the author (may be individual or organization) and/or publisher?

  • What are the credentials and affiliation or sponsorship of any named individuals or organizations?
  • How objective, reliable, and authoritative are they?
  • Have they written other articles or books?
  • Is the author(s) listed with contact information (street address, e-mail)?
  • Has the publisher published other works?
  • Do they specialize in publishing certain topics or fields?
  • Is the publisher scholarly (university press, scholarly associations)? Commercial? Government agency? Self (“vanity”) press?

What can be said about the content, context, style, structure, completeness and accuracy of the information provided by the source?

  • Are any conclusions offered? If so, based on what evidence and supported by what primary and secondary documentation?
  • What is implied by the content?
  • Are diverse perspectives represented?
  • Is the content relevant to your information needs?

When was the information published?

  • Publication date is generally located on the title page or on the reverse side of the title page (copyright date).
  • Is the information provided by the source in its original form or has it been revised to reflect changes in knowledge?
  • Is this information timely and is it updated regularly?

Where else can the information provided by the source be found?

  • Is this information authentic?
  • Is this information unique or has it been copied?

Why was the information provided by the source published?

  • What are the perspectives, opinions, assumptions and biases of whoever is responsible for this information?
  • Who is the intended audience?
  • Is anything being sold?


Where to Look for Answers

Books and Articles

An initial evaluation of books and articles can be done by examining their bibliographic citations provided in library online catalogs or article databases, containing brief author, publisher and date of publication information. Once you have found the book or article, look for additional information about the author(s) or publisher. If little or no biographical information is provided about the author(s), ask a reference librarian for assistance.  Librarians can also help you find book reviews, or you can take a look at our research guide to book reviews.


Ideally, websites will include the following elements which can be used in the evaluation process:

  1. Author or contact person with addresses (street, e-mail)
  2. Document Uniform Resource Locator (URL), including an institutional identifier (e.g., an edu with a URL identifies the sponsoring institution as an educational institution)
  3. Date of creation or revision
  4. Link to sponsoring institution Web site


For more information on evaluating websites, see:


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Location: Library Addition, 1st Floor
Phone 619.594.6728  Text: 619.567.9743

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