As you are conducting public health, medical, or nursing research, you will rely on both primary and secondary data sources. It is important to recognize the literature type that you are consulting.
When delineating between primary and secondary literature, consider the relationship of the principal investigator to the data that is being reported. For example, if a team of researchers conducts a clinical trial on the effectiveness of a new medication, they have had a direct role in generating a hypothesis, running the study, collecting data, and then producing a publication from their clinical work. This example represents a primary study because the researchers have a direct, tangible role in the data generation and collection process. Once this example study’s findings are published, if another researcher were to use the data collection by the initial investigators for their own research, this would represent a secondary research study.
When determining a source's primary or secondary status, it is important to remain vigilant during your reading. The lists below are a suggested starting point. For example, a book might contain primary research results, in addition to secondary data. Likewise, researchers conducting a clinical trial commonly use secondary data to generate a hypothesis, but then generate their own primary data during their study. When reading a clinical trial, data presented in the "literature review" component is secondary, the researchers' findings are primary.
Primary sources provide data from a specific research study. Primary studies require a principal investigator or investigative team, often require grant funding, and are associated with a “hands-on” research experience. Primary research studies and their associated data prove real-time insights into a specific research question.
Examples of primary sources include:
Secondary sources use data collected from government organizations, and will also include publications that examine, review, or analyze data collected by someone else. Because secondary sources rely on data collected by someone else, an outside entity, at an earlier time, secondary studies rely on past, not current data.
Examples of secondary sources include: