Evaluation of Information Sources
Part II, Evaluation Criteria


This tutorial is intended to give you a foundation in the evaluation of Information Sources. Once you find information, you need to evaluate it, to determine it's value with respect to your information needs. This tutorial is presented in two parts. Part I will discuss understanding what type of information source you have and Part II will cover the criteria by which you may evaluate an information source.

When you have any item of information you should critically evaluate it to determine it's suitability to your needs, and the value of the information. This applies no matter what format it might be in, including a story told by your Mother, found on the Internet, or an article in a major journal. There is no one test which you may use to judge your information's value, but there are a number of clues, or criteria, you should use to base a judgment.

There are five basic criteria to consider.
  1. Authority
  2. Reliability
  3. Currency
  4. Completeness
  5. Relevancy


Where did the information come from? Did it come from an authority in the field?

Authority should be judged on both the author and the publisher of the material
  • Is the author's name available?
  • What is the author's training, education, experience in the field?
  • Are there other works by this author in this field? Books, articles?
  • Does the author have a reputation in the field - good or bad?
  • If your information source is a web site, this might be harder to figure out. Is there an author or contact person listed, and is there a contact e-mail address available. It could be at the top of the page with the title, or at the bottom of the page.
  • Is the Publisher well known in the field?
  • How much do they publish?
  • Is this a "vanity press" where anyone can have something published, for a fee?
  • Is it a university press?
  • Is the publisher a professional organization or association?
Generally, you can assume that known publishing houses, university presses, and professional organizations will publish quality materials.


How reliable is this information source? Can you trust and believe it?

Reliability is directly related to Authority, but does address different issues. Reliability in this context relates to the accuracy and treatment of the information.

  • Is the information correct, as far as you can tell? Look at several information sources and compare them.
  • Does the author cite his or her sources? Does it have a complete bibliography?
  • Were primary or secondary sources used?
  • Does it appear to be well edited? Do you see poor grammar, nonstandard language or misspelled words?
  • If your information source is a web site, what is the origin of the source? The domain, or last part of the web address, can tell you something about its origin. The most common are:
    • .edu - an educational institution
    • .gov - a government agency
    • .com - a commercial entity
    • .org - a not-for-profit organization
Keep in mind that while .com sites might provide valid information, they are probably more interested in selling something. How reliable is this information source? Can you trust and believe it?

Objectivity or Bias
  • Do you detect a bias on the part of the author in the writing?
  • Do the facts support the viewpoint of the author?
  • Is it written from an objective viewpoint, or does it appeal to emotions or biases?
  • Is the information presented as facts, which can be documented, or opinions of the author?
Bias is not necessarily a bad thing; we all have our own opinions and biases. But you should be aware of them, and take that into consideration when looking at an information source. The National Rifle Association of America and The Brady Campaign to Prevent Gun Violence will both give you accurate facts and statistics, but the way they are presented - the bias of the source - will present very different information.


How old is this information? Is there newer information available?
  • When was the information published?
  • Can you tell when it was published? If it is not dated, you should be cautious of the information source.
  • Is that information up-to-date? Have new discoveries been made, or have events taken place since the information was published?
  • Is your topic one which is changing quickly, such as medical research or technology, or one which is fairly stable and requires more background information such as history or literature?
  • If your information source is a web site, the date of publication and/or last updated date are usually found at the bottom of the page.


Is the information the most complete available? Is it comprehensive? Who is it written for?
  • Is the information complete, or is it a summary of other work?
  • Is the subject covered completely?
  • What level is the information? Is it advanced, technical, basic information?
  • Who is the intended audience for the material? Is it popular or scholarly?
  • If your information source is a web site, does it include links and are they annotated?


After all is said and done, does the information source answer your questions? Does it "fill your information need?"

While the other criteria are based on facts, things you can see or find out about your information source, this one is a total judgment call. You must know what information you need, what type of information source you need it to come from, and what you will be using that information for (a final term paper, a short composition, your personal knowledge or information, etc.).

You must make the judgment as to the relevancy of your information source. Is the information source relevant to your information need?

It is entirely possible, and highly likely that you will find an item which is very reliable, from a very authoritative source, very current, and very complete... but not relevant to your topic.


Remember, always evaluate what you see, hear or find. This applies not just to information you go out looking for, but also any information which finds its way to you - you know, fliers on the corner, chain letters in your e-mail, or newspaper reports.

What kind of information is it; primary, secondary, popular, scholarly? Is it from an authority? Is it from a reliable source? Is it current? Who is the intended audience and is it the complete information? And finally, is it relevant to you?

The End!