Dartmouth's Evidence Pyramid provides a way to visualize both the quality of evidence and the amount of evidence available. For example, systematic reviews are at the top of the pyramid, meaning they are both the highest level of evidence and the least common. As you go down the pyramid, the amount of evidence will increase as the quality of the evidence decreases. Image credit: EBM Pyramid by Trustees of Dartmouth College and Yale University.
Here's another take on the evidence pyramid indicating primary vs. secondary sources and explaining each level.
Research methods are the strategies, processes or techniques utilized in the collection of data or evidence for analysis in order to uncover new information or create better understanding of a topic. There are different types of research methods which use different tools for data collection.
Gathers data about lived experiences, emotions or behaviors, and the meanings individuals attach to them. It assists in enabling researchers to gain a better understanding of complex concepts, social interactions or cultural phenomena. This type of research is useful in the exploration of how or why things have occurred, interpreting events and describing actions.
Qualitative research refers to any research based on something that is impossible to accurately and precisely measure. It uses methods such as interviews, open-ended questions, participant observations, case studies, focus groups, etc. to identify patterns, themes, and features. These factors cannot easily be reduced to numbers. Qualitative research is common in the social sciences.
Gathers numerical data which can be ranked, measured or categorized through statistical analysis. It assists with uncovering patterns or relationships, and for making generalizations. This type of research is useful for finding out how many, how much, how often, or to what extent. This research based on something that can be accurately and precisely measured might also be referred to as "empirical research."
Pro tip: Statistical analysis in an article usually indicates quantitative research. Check the articles you find to see if some sort of numerical measuring and statistical analysis is present along with the characteristics listed below.
Integrates both Qualitative and Quantitative Research. It provides a holistic approach combining and analyzing the statistical data with deeper contextualized insights. Using Mixed Methods also enables Triangulation, or verification, of the data from two or more sources.
Finding Mixed Methods research in the Databases
"mixed model*" OR "mixed design*" OR "multiple method*" OR multimethod* OR triangulat*
Usually focuses on a single, well-defined research question and seeks to comprehensively gather all existing studies that address this research question.
Takes the results of several existing quantitative studies and analyzes them in a new way. Meta-analysis looks for previously unnoticed patterns or trends among existing study results or seeks to pull out new data from them. Meta-analysis is usually considered another form of quantitative research.
Also known as a review article, is an article whose sole purpose is to provide an overview of previous important research on a particular topic. Although valuable to researchers, literature reviews are not considered primary research. However, they can help you identify research trends and major articles published on a topic. No new study is conducted in a true literature review.