How to evaluate information resources
Pre-evaluation
You can do a preliminary evaluation of a source by using the descriptions available in an article index or library catalogue. Before you click on the full text of the article or go to the shelf to find the book, use the following information to help you decide whether the item is worth pursuing.
- Content: The title, abstract, subject headings, and table of contents can all provide valuable information about the item, which will help you to determine if it is relevant to your topic.
- Publication information: The publisher, place, and date of publication can be very important for some topics. For example, a book about computers written in 1975 might not be as useful as one written in 2015!
- Physical description: The length of an item can be important. For example, If you are looking for an in-depth analysis of a subject, a 2-page magazine article probably won't be useful.
Evaluation
Once you have a copy of the source, analyze it using the criteria below.
Relevancy
- This may seem obvious, but is the information provided actually useful for your assignment? Determine if the source fully or only partially covers your topic. "Fully" is best, but sometimes you have to work with "partially".
- Hint - looking at the introduction, conclusion, bibliography and table of contents of a work takes little time and can go a long way towards determining relevancy.
Authority/Reliability
- The knowledge and credibility of the author is very important. You must decide if an author has the credentials to be writing on the topic.
- Determine if the author is affiliated with a university or institution. Has your instructor mentioned the author?
- As an example, if the author is a professional journalist, he/she might be a very good writer, but not have the background to write extensively on the topic.
Accuracy/ Validity
- Often accuracy and validity are hard to determine if you aren't familiar with a topic, but ask yourself if the conclusions reached by the author are supported by the evidence used.
- As an example, if a source asserts that the earth is flat, is there evidence (e.g., surveys, maps) to back the argument up?
- Look for obvious omissions - is only one side of a topic discussed?
- See if there are typographical errors (spelling mistakes, poor grammar, etc.).
- Check to see if external sources were consulted and properly cited.
Audience
- Is the work intended for scholars, professionals, or the general public?
- You must determine if the level of content is appropriate for your information needs. To detailed/specialized? To general/simple?
- As an example, while you wouldn't write a university paper on volcanoes using websites designed for high school students, you also don't want to use sources so complicated that you don't fully understand them.
Scholarly versus popular periodicals
A scholarly journal is generally one that is published by and for scholars. Scholarly journal articles will almost always
- present original or previously unpublished research
- contain information on the author (including academic credentials & affiliations)
- contain footnotes and a bibliography
A popular magazine is one published for the general public. Popular magazine articles tend to
- synthesize information and research presented elsewhere
- be shorter in length and contain pictures and advertisements
- be written by staff writers or reporters whose credentials are not listed
A popular book is also published for the general public or, often, for a non-academic audience. Popular books are often:
- written for an author with no scholarly affiliation or expertise
- written at a general or non-specialized reading level, often containing no references to consulted sources. Because popular books are written for the general public, for younger audiences, or for non-academic audiences, they generally contain no scholarly language or terminology related to a specific academic specialty or discipline.
- published by popular presses as opposed to scholarly or university presses.
See also: How to identify scholarly, trade and popular publications
Evaluating web pages
While the evaluation criteria above can be used to evaluate any information source, including webpages, the Internet provides some unique challenges. Some of the reasons webpages are so difficult to evaluate are:
- Anyone can publish anything on the Internet
- Rarely is there any quality assurance e.g. editors, fact-checkers, peer review, librarians
- It can be difficult to find traditional evaluation elements on the Web e.g., author, publisher, publication date.
See How to evaluate web pages for detailed help.