Because there are several categories of sources (see Types of Sources), the options you have to meet your information needs can seem complex.
Our best advice is to pay attention to when only primary and secondary sources are required to meet a need and to when only professional and scholarly sources will work. If your research project is in the arts, also pay attention to when you must use popular sources, because popular sources are often primary sources in the arts.
These descriptions and summaries of when to use what kind of source should help.
To Learn Background Information
When you first get a research assignment and perhaps for a considerable time afterward, you will almost always have to learn some background information as you develop your research question and explore how to answer it.
Sources from any category and from any subgroup within a category – except journal articles – can meet your need to learn background information and understand a variety of perspectives. Journal articles are usually too specific to be background information. From easy-to-understand to more complex sources, read and/or view those that advance your knowledge and understanding.
For instance, especially while you are getting started, secondary sources that synthesize an event or work of art and tertiary sources such as guidebooks can be a big help. Wikipedia is a good tertiary source of background information.
Sources you use for background information don’t have to be sources that you cite in your final report, although some may be.
One important reason for finding background information is to learn the language that professionals and scholars have used when writing about your research question. That language will help you later, particularly when you’re searching for sources to answer your research question.
To identify that language, you can always type the word glossary and then the discipline for which you’re doing your assignment in Google.
Here are two examples to try:
Putting a phrase in quotes in most search boxes ensures that the phrase will be searched rather than individual words.
To Answer Your Research Question
You have to be much pickier with sources to meet this need because only certain choices can do the job. Whether you can use quantitative or qualitative data depends on what your research question itself calls for.
Only primary and secondary sources can be used to answer your research question and those need to be professional and/or scholarly sources for most disciplines (humanities, social sciences, and sciences). But the arts often require popular sources as primary or secondary sources to answer research questions. Also, the author’s purpose for most disciplines should be to educate and inform or, for the arts, to entertain and perhaps even to sell. Keep in mind that primary sources are those created at the same time as an event you are researching or that offer something original, such as an original performance or a journal article reporting original research. Secondary sources analyze or otherwise react to secondary sources. Because of the information lifecycle, the latest secondary sources are often the best because their creators have had time for better analysis and more information to incorporate.
Suppose your research question is “How did a particular king of Saudi Arabia, King Abdullah, work to modernize his country?”
That question may lend itself to qualitative descriptive judgments—about what are considered the components of modernization, including, for instance, what were his thoughts about the place of women in society.
But it may also be helped by some quantitative data, such as those that would let you compare the numbers of women attending higher education when Abdullah became king and those attending at the time of his death or, for instance, whether manufacturing increased while he reigned.
So looking for sources that provide both quantitative and qualitative information (not necessarily in the same resource) is usually a good idea.
If it is not clear to you from the formats of sources you are assigned to read for your course, ask your professor which formats are acceptable to your discipline for answering your research question.
Sources to Answer Your Research Question
- Quantitative or Qualitative: Will be determined by the question itself.
- Fact or Opinion: Professional and scholarly for most disciplines; the arts often use popular, as well.
- Scholarly, Professional, or Popular: Professional and scholarly for most disciplines; the arts often use popular, as well.
- Primary, Secondary, or Tertiary: Primary and secondary.
- Publication Format: Those acceptable to your discipline.
To Convince Your Audience
Convincing your audience is similar to convincing yourself and it takes the same kinds of sources—as long as your audience is made up of people like you and your professor, which is often true in academic writing. That means using many of those sources you used to answer your research question.
When your audience isn’t very much like you and your professor, you can adjust your choice of sources to meet this need. Perhaps you will include more that are secondary sources rather than primary, some that are popular or professional rather than scholarly, and some whose author intent may not be to educate and inform.
Sources to Convince Your Audience
- Quantitative or Qualitative Data: Same as what you used to answer your research question if your audience is like you and your professor. If you have a different audience, use what is convincing to them.
- Fact or Opinion: Those with the purpose(s) you used to answer your research question if your audience is like you and your professor. If you have a different audience, you may be better off including some sources intended to entertain or sell.
- Scholarly, Professional, or Popular: Those with the same expertise level as you used to answer the question if your audience is like you and your professor. If you have a different audience, you may be better off including some popular sources.
- Publication Mode: Primary and secondary sources if your audience is like you and your professor. If you have a different audience, you may be better off including more secondary sources than primary.
- Publication Format: Those acceptable to your discipline, if your audience is like you and your professor.
To Describe the Situation
Choosing what kinds of sources you’ll need to meet this need is pretty simple—you should almost always use what’s going to be clear and compelling to your audience. Nonetheless, sources intended to educate and inform may play an out-sized role here.
But even then, they don’t always have to educate and inform formally, which opens the door to using sources such as fiction or the other arts and formats that you might not use with some other information needs.
Sources to Describe the Situation
- Quantitative or Qualitative: Whatever you think will make the description most clear and compelling and your question important to your audience.
- Fact or Opinion: Often to educate and inform, but sources don’t have to do that formally here, so they can also be to entertain or sell.
- Scholarly, Professional, or Popular: Whatever you think will make the description most clear and compelling and your question important to your audience.
- Primary, Secondary, or Tertiary: Whatever you think will make the description most clear and compelling and your question important to your audience. Some disciplines will not accept tertiary for this need.
- Publication Format: Whatever you think will make the description most clear and compelling and your question important to your audience. Some disciplines will accept only particular formats, so check for your discipline.
To Report What Others Have Said
The choices here about kinds of sources are easy: just use the same or similar sources that you used to answer your research question that you also think will be the most convincing to your audience. Look for sources about how others have treated your research question