Most sources fall into two categories: scholarly and popular. Understanding the difference between a scholarly and popular source is a crucial step in evaluating sources for your research.

Scholarly sources are written by highly-qualified researchers and have a thorough publication process, which usually involves peer-reviewing and an extensive list of references at the end of the text. They often have a specific audience in mind, most likely other experts in the particular field of study. Examples of scholarly sources include books and academic journals written by scholars and experts.

Popular sources, on the other hand, are written by and intended for a general audience. Popular sources are not peer-reviewed, and they do not usually include a reference list. Examples of popular sources range from some books and magazines to websites and blogs.

Peer Review

Below are some questions to ask and things to consider as you read through a source.

Find out what you can about the author

 One of the first steps is to locate more information about the author. Sometimes simply typing an author's name into a search engine will give you information. Learning the author's educational background and areas of expertise will help you determine if the author has experience in what they are writing about. 

Ask yourself:

• Who wrote this?
• What are their credentials?

Determine the intended audience

Consider the tone, style, vocabulary, level of information, and assumptions the author makes about the reader. Are they appropriate for your needs? Remember that scholarly sources often have a very particular audience in mind, and popular sources are written for a more general audience. 

Ask yourself:

• Why does this exist?
• Can I understand the author's message? Is the information too simple for my research needs?

Determine whether the information is fact, opinion, or propaganda

Information can usually divided into three categories: fact, opinion, and propaganda. Facts are objective, while opinions and propaganda are subjective. A fact is something that is known to be true.  An opinion gives the thoughts of a particular individual or group. Most peer-reviewed research is opinion. Propaganda is the spreading of information for a specific person, group, event, or cause.  It relies on slogans or emotionally charged images to influence an audience. Propaganda can also involve the selective reporting of true information in order to deceive an audience.

Examples:

• Fact: The earth is round.
• Opinion: We can use virtual reality to show how the earth is spherical.
• Propaganda: When I walk on the planet's surface, it looks and feels flat, so the earth must be flat. 

Note the difference between opinion and propaganda is that propaganda usually has a specific agenda attached--it is being spread for a certain reason or to accomplish a certain goal.

Ask yourself:

• Is the language objective or emotional? Objective language tends to stick to facts, but emotional language relies on garnering a response from the reader.
• If the source appears to represent an opinion, does the author offer legitimate reasons for adopting that stance?
• If the opinion feels one-sided, does the author acknowledge opposing viewpoints? How so?

Evaluate the evidence

Seeing what the author has cited as evidence can help determining the source's authority and whether the information is fact, opinion, or propaganda.  If you’re reading an opinion-based source, ask yourself whether there’s enough evidence to back up the opinions. If you’re reading a fact-based source, be sure that it doesn’t oversimplify the topic. The more familiar you become with your topic, the easier it will be for you to evaluate the evidence in your sources.

Check for a list of references or other citations that look as if they will lead you to material that would be good sources. If a source has a list of references, it often means that the source is well-researched and thorough.

Ask yourself:

• Does the author they give me proof? 
• Can information be verified through footnotes or bibliographies to other credible sources?
• If the author lists specific dates or facts, can you find the same information somewhere else?

Check the timeliness of the source

How recent was the source published? Some information becomes dated when new research is available, but older sources of information can still be useful and reliable fifty or a hundred years later. For example, if you are researching a scientific topic, you will want to be sure to have the most up-to-date information. However, if you are examining an historical event, you may want to find primary sources from the event, requiring older sources.

Ask yourself:

• Is it clear when the information was published and when was it last updated?
• Are there more recent events that might color the information's findings?