Evaluating Sources
Research does not only involve finding sources, but also involves evaluating sources. No source should be used just because one finds it. Analyzing and evaluating sources and the information they contain are essential parts of the research process. Every source (including this one) needs to be analyzed and evaluated to make sure it is an appropriate and trustworthy source.
The two main points one needs to analyze are the reliability of the source and the validity of the content. For the reliability of the source one needs to judge whether or not the author and the type of source can be trusted to provide dependable information. To judge the validity of the content, one needs to analyze if what the source is saying is correct and appropriate.These concepts can be applied to both print sources and electronic sources. Below are some pointers and questions to consider when analyzing sources.
Evaluating Print Sources
Reliability of the Source
Author
- Are the author's credentials listed? Is anything included in the source which lists the author's educational or professional background?
- Is there any available background or biographical information about the author? The Reference area in the TLU Library contains several resources for locating biographical information.
- Has the author written anything else in the same or similar fields? Does WorldCat list any other books by the author? Or, does Google Scholar or one of the library databases list additional articles by the author?
Source
Books. Who is the publisher? Is the book published by a university press, a major press, or an organization? Are there any book reviews on the book? Several of the library databases (
Academic Search Complete, for example) allow you to limit your search to book reviews. How do others analyze the book?
Periodicals. In what type of periodical is the article published? Is it a popular magazine such as
Time or
Newsweek? A newspaper? A peer-reviewed scholarly journal? Different types of periodicals provide different levels of information.
Top Validity of the Content
Purpose
Things are written for a purpose. By looking for and recognizing the reason the content was written, one has a better understanding of the work. When looking for the purpose of a source, one should ask:
- What is the purpose of the work?
- Is the work written from a particular point of view?
- What is the author's bias?
- Who is the intended audience?
Verification
It is important to verify the information. When looking to verify information, one should ask:
- Can the information be verified in another source or by personal knowledge?
- Are the basic facts the same in more than one source?
- Has there been any reaction to the author's claims?
Documentation
Authors should give credit where credit is due. Supplying a list of sources is important for any work. A list of sources makes it easy to verify the information.
- Does the author document the information?
- Are the author's claims supported by additional sources and facts that can be verified?
- Does the author provide a bibliography?
Accuracy
Authors need to use accurate information. They also need to use other sources accurately. Without the correct information, the author's claims might not be true; therefore, one needs to ask:
- How accurate is the information?
- Does the author provide proof for his/her claims?
- Does the author quote other authors correctly?
- Are other authors saying similar things?
Currency
Look in the bibliography and see how current the sources are. For some topics, especially in the sciences, current information is very important. In other topics (history, for example), currency is not quite as important, but even in these areas, authors still need to be aware of the current ideas and trends in their field. Therefore, one needs to pay attention to the currency of the sources the author cites and ask the following questions:
- How current is the information?
- Is the author using current sources?
- Is the author trying to pass off old information as new and current?
Top Evaluating Electronic Sources
Library Databases What is the difference between
library databases and the rest of the Internet? Unlike information found on the "open" Internet, most print sources have gone through some evaluation by a publisher before they have been published. Most of the sources in library databases are electronic versions of print sources. The full-text articles one finds through the library databases are the same as the articles found in the printed journal or magazine. Although library resources can be accessed through the Internet, in general, library resources are on the "closed" Internet. For these reasons, sources found on the library databases can be evaluated as if they were print sources.
Evaluating Internet Sources Evaluating sources from the "open" Internet (freely accessible) is harder than evaluating print sources. This is true for several reasons:
- Because anyone can publish a Web site, it is harder to find out who the author is and what his/her credentials are.
- Internet sources are much more fluid in that the information posted on a Web site can change in an instant.
- Often the content has not been evaluated before it is posted to the Web site. Therefore, one needs to take extra precaution when using information found on the "open" Internet. There is a lot of reliable information available on the Internet but much of it is suspect. One needs to be able to judge the information and sort the good from the bad.
Top Reliability of the Source
URLs
The URL (Uniform Resource Locator) often provides valuable information about the origin of the site. By examining the URL, one can get some idea of where the source originated. Often the URL will include the name or abbreviation of the organization hosting the site. For example, the
www.tlu.edu URL contains "tlu" (Texas Lutheran University). The URL always includes the "domain" of the site, which indicates the kind of organization hosting the site. Domains are expanding but here are a few examples:
- .com .net .org .info - open to anyone
- .biz .name . pro - unrestricted, unsponsored, but intended for business purposes
- .aero .cat .coop .jobs .mobi .museum .tel .travel - restricted or sponsored, but anyone can apply for a .tel domain
- .edu .gov .int .mil - exclusive, restricted domains
Domains assigned to countries and states are another group that allows an organization to append a two-letter code to the main domain.
Author of the Source
Is it easy to discover who wrote or created the Web site? Is that person responsible for the content of the information you want to use?
Owner/Sponsor/Publisher of the Site
- What is the purpose of the site?
- Is the site written from a particular point of view?
- What is the author's bias?
- Is the site only trying to provide information or is the site trying to sell something?
- Is it a promotional site for an organization?
- Who is the intended audience?
Validity of the Source
Purpose Things are written for a purpose. By looking for and recognizing that reason, one has better understanding of the work. When looking for the purpose of a source, one should ask:
- What is the purpose of the site?
- Is the site written from a particular point of view?
- What is the author's bias?
- Is the site only trying to provide information, or is the site trying to sell something?
- Is the site a promotional site for an organization?
- Who is the intended audience?
Verification
It is important to verify the information provided by any source. When doing so, one should ask:
- Can the information be verified?
- Are the basic facts the same in more than one source?
- Has there been any reaction to the author's claims?
Documentation
Authors should give credit where credit is due. Supplying a list of sources used is important for any work. A list of sources makes it easy to verify the information.
- Does the author document the information?
- Are the author's claims supported with additional sources and facts that can be verified?
- Does the author provide a bibliography?
Accuracy
Authors need to use accurate information. They also need to use other sources accurately. Without the correct information, the author's claims might not be true; therefore, one needs to ask:
- How accurate is the information?
- Does the author provide proof for his/her claims?
- Does the author quote other authors correctly?
- Are other authors saying similar things?
Currency
Look in the bibliography and see how current the sources are that the author uses. For some topics, current information is very important. In other topics, currency is not quite as important but even in these areas, authors still need to be aware of the current ideas and trends. Therefore, one needs to pay attention to the currency of the sources the author uses and ask the following questions:
- How current is the information?
- Is there any indication of the last time the site was updated?
- Is the author using current sources?
- Is the author trying to pass off old information as new and current?
Top Bibliography and Additional Guides
Criteria for Evaluation of Internet Information Resources (Alastair Smith, Victoria U of Wellington, New Zealand)
Critically Analyzing Information Sources (Cornell U)
Evaluating Information: Applying the CRAAP Test (California State U, Chico)
Evaluating Information Found on the Internet (Elizabeth E. Kirk, Johns Hopkins U)
Evaluating Information Resources: Criteria to Consider (Illinois State U)
ICYouSee: T Is for Thinking (John R. Henderson, Ithaca College Library)
Web Page Checklist (Binghamton University Libraries)
Why We Need To Evaluate What We Find on the Internet (Purdue U Libraries)
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Page Maintainer: Sally Carroll-Ricks, MLS, MM, AHIP
Library Systems Administrator/E-Resources Librarian
Last modified: October 6, 2009, by scr 
