Does your research assignment specify whether you need to include journal articles in your bibliography? Maybe you want to include images or maps as sources of evidence in your research. If so, you can use search filters in the Library catalog or subject databases to limit your results to certain types of information resources (ex., articles, books, films, images, datasets).
In the Health Sciences, it is preferable to incorporate studies and experiments conducted within the past five years. However, when conducting historical research, it is preferable to include information sources published in the same time period as the events you are investigating. You can use search filters in the Library catalog or subject databases to limit your results to certain publication dates or date ranges (ex., 2020-2025).
A peer-reviewed source is an article that has been reviewed by several other experts in the field before being published in order to ensure its quality. This 2-minute video describes the peer review process.
Many databases allow you to specify that you want to search only in “peer-reviewed” or “refereed” sources.
Search online for your journal’s title. Sections like “about this journal” or “editorial policies” generally mention whether the journal is peer-reviewed/refereed.
Use the Ulrich’s Periodicals Directory to find key information about a journal, including whether it has a peer-review process.
A primary source is an original object or document created during the time under study. Primary sources vary by discipline and can include historical and legal documents, diaries, letters, family records, speeches, interviews, autobiographies, film, government documents, eyewitness accounts, results of an experiment, statistical data, pieces of creative writing, and art objects. In scientific and social science disciplines, the results of an experiment or study are typically found in scholarly articles or papers delivered at conferences, so those articles and papers that present the original results are considered primary sources.
A secondary source is written to summarize, synthesize, or analyze a primary source. Secondary sources include comments on, interpretations of, or discussions about the original material. In the sciences, secondary sources are often reviews (e.g., systematic reviews, umbrella reviews, meta-analyses) that gather original research studies and experiments to provide analysis in the aggregate. Secondary source materials can be articles in newspapers or popular magazines, book or movie reviews, or articles found in scholarly journals that evaluate or criticize someone else's original research.
Many databases allow you to specify that you want to search for "empirical” or “original” research studies. Other databases will have filters for experimental design methods such as "randomized control trials" or "brain imaging" that will enable you to limit results to primary resources.
Primary research articles:
Scholarly resources, such as journals, academic books, and dissertations, undergo a formal evaluation process before publication. This helps to ensure high-quality information and accuracy of results with sound methodology and ethical considerations that adhere to "best practices" within a field of research.
Popular resources do not typically go through the same review process as academic resources. In many cases popular resources are reviewed by a single editor, who may or may not have expertise in the subject area. Popular resources are usually written for a broad audience and do not always use the same, formal language as authors of academic articles. Examples of popular resources include magazine and newspaper articles, websites, and wikis. Use popular resources to identify the latest trends and issues within your topic, but do not rely heavily on these types of resources.
Grey literature is information produced outside of traditional publishing and distribution channels and can include technical reports, policy literature, working papers, newsletters, government documents, speeches, white papers, urban plans, and so on.
This short video explains the differences between a scholarly and a popular resource.