In general, quantitative research seeks to understand the causal or correlational relationship between variables through testing hypotheses, whereas qualitative research seeks to understand a phenomenon within a real-world context through the use of interviews and observation. Both types of research are valid, and certain research topics are better suited to one approach or the other. However, it is important to understand the differences between qualitative and quantitative research so that you will be able to conduct an informed critique and analysis of any articles that you read, because you will understand the different advantages, disadvantages, and influencing factors for each approach.
The table below illustrates the main differences between qualitative and quantitative research. Important Note: These are generalizations, and not every research study or article will fit neatly into these categories.
|
Qualitative |
Quantitative |
Keywords |
Complexity, contextual, inductive logic, discovery, exploration |
Experiment, random assignment, independent/dependent variable, causal/correlational, validity, deductive logic |
Purpose |
Understand a phenomenon |
Discover causal relationships or describe a phenomenon |
Sample |
Purposive sample, small |
Random sample, large |
Data |
Focus groups, interviews, field observation |
Tests, surveys, questionnaires |
Methods/ Design |
Phenomenological, grounded theory, ethnographic, case study, historical/narrative research, participatory research, clinical research |
Experimental, quasi-experimental, descriptive, methodological, exploratory, comparative, correlational, developmental (cross-sectional, longitudinal/prospective/cohort, retrospective/ex post facto/case control) |
Systematic reviews, meta-analyses, integrative reviews, and scoping reviews are not exactly designs, but they synthesize, analyze, and compare the results from many research studies and are somewhat quantitative in nature. However, they are not truly quantitative or qualitative studies.
References:
LoBiondo-Wood, G., & Haber, J. (2014). Nursing research: Methods and critical appraisal for evidence-based practice (8th ed.). St. Louis, MO: Mosby Elsevier.
Melnyk, B.M., & Fineout-Overholt, E. (2019). Evidence-based practice in nursing & healthcare: A guide to best practice (4th ed.). Wolters Kluwer.
Much of the content on this page was borrowed from and used with permission of the Stevenson University Library.
Not all research studies and articles are 100% qualitative or 100% quantitative. A mixed methods study involves both qualitative and quantitative approaches. If you need a study that's purely qualitative or purely quantitative, look carefully at the methodology section of the article to see if it used a single method or a combination of methods.