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Guide to Information Retrieval LAB

Evaluating information critically

The problem with information these days is not finding it, as there is plenty of information out there, but rather how to find and choose the best information sources out of all the information available. One of the key skills of information literacy is the ability to evaluate the quality of information sources and being able to identify different source types.

In higher education the sources you use for your assignments and thesis should be reliable and of high quality. This means that you need to think critically about the information you find and evaluate the sources before using them. Here are some criteria that should keep in mind when you when you evaluate your information sources: currency, relevance, accuracy, authority and purpose. These criteria are also known as the CRAAP test, which was originally devised by Meriam Library at California State University Chico.


Currency refers to the timeliness of information. In some fields information becomes outdated quicker than in others, for example medicine and engineering can change quickly due to new research and information technology so you should always use the newest information available. Having said that nearly all fields have their classics that stand the tests if time where publication year isn’t an issue.

Here are a few questions to consider when determining the currency of your source:

  • When was the information published or posted online?
  • Has it been revised or updated?
  • Are the sources used in the publication up-to-date?
  • Are the links are functional?


Relevance refers to the importance of the information for your needs. If you are after basic information like the train times then you probably won’t need multiple information sources, but when you are looking for information for your assignments or thesis you should look at several sources to gain a better and wider understanding of the topic. You also need to determine what level of information is suitable for your information needs. Remember that you shouldn’t use theses as information sources for your own thesis or assignment. 

Here are a few questions to consider when determining the relevance of your source:

  • Does the information relate to your topic or answer your question?
  • Is the information at an appropriate level (not too elementary or too advanced)?
  • Have you looked at a variety of sources before deciding on which to use?


Authority refers to the source of the information. The publisher and the publication usually give some indication about the quality and reliability of the information, for both print and electronic materials. You should always be critical about self-published material as it doesn’t go through the same quality control as materials published through publishing houses.

You should also pay attention to who the author is, when you are evaluating authority. You can determine if they are qualified to write about the topic by checking their level of education (someone who has just graduated is rarely an expert in their field and that’s why you shouldn’t use thesis as a source for your essays) or professional experience. You can also check if the author has published other books or articles in the same field. Some databases will also tell you how many times the article or book has been cited by others. A high number of citations usually tells that the article/author is well-known and respected in that particular field.

Websites can also be credible and informative sources, for example organizations like World Health Organization (WHO) and Statistics Finland check their facts before posting them online. But it’s always good to keep in mind that anyone can publish anything online so there is a lot of dubious material out there.  Remember to be critical about the information you find online.

Here are a few questions to consider when determining the authority of your source:

  • Who is the author/publisher/source?
  • What are the author’s credentials or organizational affiliations?
  • Is the author qualified to write on the topic? Are they a professional or published academic or a lay person expressing their own views on the subjects?   See more >
  • Does the URL reveal something about the website?


Accuracy refers to the reliability, the truthfulness and the correctness of the content. You can use your prior knowledge to determine the accuracy of information or you can compare the information to other sources to see if it holds. You should check if the author uses references to back up their claims. Remember that you should always use peer reviewed or refereed material for your assignments and your thesis.                  

Here are a few questions to consider when determining the accuracy of your source:

  • Where does the information come from?
  • Is the information supported by evidence?
  • Has the information been reviewed or refereed before publishing?
  • Can you verify any of the information from another source?
  • Are there spelling, grammar or typographical errors?


Purpose refers to the reason the information exists. Information is produced for different purposes, it can teach, entertain, sell, inform, and influence opinion. It’s advisable to consider the agenda behind the information that you are evaluation, as it gives you a better understanding about the quality of the information and whether or not its biased.

Here are a few questions to consider when determining the purpose of your source:

  • What is the purpose of the information?
  • Is the information fact, opinion or propaganda?
  • Do the authors/publishers make their intentions or purpose clear? 
  • Does the point of view appear objective and impartial, or is the information sponsored/produced by someone with an agenda?

Know your periodicals

The publication type usually gives a good indication about the purpose of the material. For example text books are usually published to educate, doctoral thesis contain new information and popular magazines are there to entertain. Being able to identify different types of publications is an important part of information literacy. Text books, novels and doctoral thesis are relatively easy to identify, whereas different types of periodicals can be trickier to tell apart. Periodicals can be divided into four categories: newspaper, popular magazines, professional, trade&industry journals and scholarly&research journals.

Popular magazines are usually written by journalists or freelance writers, not academics or experts of the in the field. The language in popular magazines is non-technical. The articles rarely cite any sources. Popular magazines are intended for the general public. Popular magazines shouldn’t be used as sources for your assignments or thesis. The Economist and Time magazine are examples of popular magazines.

Newspapers are written by journalists. The language of newspapers is non-technical. Newspaper articles rarely cite sources in full. Newspapers are aimed for a general educated audience. Newspapers contain current information, local and regional information, editorials, classified ads and reviews. Wall Street Journal and Helsingin Sanomat are examples of newspapers.

Professional, trade&industry journals are written by practitioners in the field or by journalists with subject expertize. The language in these journals can contain extensive jargon and sources are sometimes but not often cited in the text. Articles from trade journals are usually short, about 2-3 pages. The articles discuss current trends, news and products in a field. Goldsmiths’ review and Auto&design are examples of trade magazines. 

Scholarly journals are written by experts and academics. The language used in scholarly journals is academic and technical. Specialized vocabulary of the discipline is often used. Articles in scholarly journals often follow the IMRD-format: introduction, methods, results and discussion. The articles always contain bibliography and in-text references. Scholarly journals contain reports of original research, in-depth analysis of issues related to the discipline and academic level book reviews. Academic journals are peer reviewed. You should use scholarly journals in your assignments.


What's wrong with Wikipedia, you might ask. It's open access and has loads of information on everything. True, some Wikipedia entries might be valid and of high quality, but do keep in mind that anyone can write and edit the articles on there. Wikipedia doesn't have a formal peer review process, nor does Wikipedia give any guarantee of the validity of its content, read more on the subject > general disclaimer

Peer review

You can think of peer review as a "stamp of approval" from academic experts. When an article is published in a peer-reviewed journal, you'll know that experts in the relevant field have read the article and, independent of their own particular opinions, verified it to meet a high standard of scholarship. Peer reviewed journals are occasionally also called scholarly or refereed journals depending on the publisher. You should use peer reviewed article in your assignments and thesis.