Non-Experimental Research
Non-Experimental Research
Not all nursing questions can be answered through experiments. Sometimes, ethical or practical limits prevent manipulation of variables, yet we still need evidence to guide care.
What is Non-Experimental Research?
Non-experimental research is research that lacks the manipulation of an independent variable. Rather than manipulating an independent variable, researchers conducting non-experimental research simply measure variables as they naturally occur (in the lab or real world). For example, a nurse researcher might explore whether nurses who work night shifts report higher stress levels than those on day shifts, without manipulating work schedules.
When to Use Non-Experimental Research?
As we saw in the last section, experimental research is appropriate when the researcher has a specific research question or hypothesis about a causal relationship between two variables—and it is possible, feasible, and ethical to manipulate the independent variable. It stands to reason, therefore, that non-experimental research is appropriate—even necessary—when these conditions are not met. There are many times in which non-experimental research is preferred, including when:
- the research question or hypothesis relates to a single variable rather than a statistical relationship between two variables (e.g., how accurate are people’s first impressions?).
- the research question pertains to a non-causal statistical relationship between variables (e.g., is there a correlation between verbal intelligence and mathematical intelligence?).
- the research question is about a causal relationship, but the independent variable cannot be manipulated or participants cannot be randomly assigned to conditions or orders of conditions for practical or ethical reasons (e.g., does damage to a person’s hippocampus impair the formation of long-term memory traces?).
- the research question is broad and exploratory, or is about what it is like to have a particular experience (e.g., what is it like to be a working mother diagnosed with depression?).
Again, the choice between the experimental and non-experimental approaches is generally dictated by the nature of the research question. Recall the three goals of science are to describe, to predict, and to explain. If the goal is to explain and the research question pertains to causal relationships, then the experimental approach is typically preferred. If the goal is to describe or to predict, a non-experimental approach is appropriate. But the two approaches can also be used to address the same research question in complementary ways. For example, in Milgram’s original (non-experimental) obedience study, he was primarily interested in one variable—the extent to which participants obeyed the researcher when he told them to shock the confederate—and he observed all participants performing the same task under the same conditions. However, Milgram subsequently conducted experiments to explore the factors that affect obedience. He manipulated several independent variables, such as the distance between the experimenter and the participant, the participant and the confederate, and the location of the study (Milgram, 1974).
Types of Non-Experimental Research
Non-experimental research falls into two broad categories: correlational research and observational research.
Correlational research is considered non-experimental because it focuses on the statistical relationship between two variables but does not include the manipulation of an independent variable. More specifically, in correlational research, the researcher measures two variables with little or no attempt to control extraneous variables and then assesses the relationship between them. As an example, a researcher interested in the relationship between self-esteem and school achievement could collect data on students’ self-esteem and their GPAs to see if the two variables are statistically related.
Correlational, Nursing Practice Example
A nurse might study whether higher patient satisfaction scores are associated with lower nurse-to-patient ratios.
Observational research is non-experimental because it focuses on making observations of behavior in a natural or laboratory setting without manipulating anything. Milgram’s original obedience study was non-experimental in this way. He was primarily interested in the extent to which participants obeyed the researcher when he told them to shock the confederate and he observed all participants performing the same task under the same conditions.
Observational Nursing Practice Example
A nurse researcher might observe communication patterns during patient handovers to identify factors that promote safety
Remixed from:
- Research Methods in Psychology by Rajiv S. Jhangiani, I-Chant A. Chiang, Carrie Cuttler, & Dana C. Leighton (2019) published by pressbooks under a CC BY-NC-SA license.
Media Attributions
- Dr. Fehr [avatar] by Research Assistant Katie Gregson on Canva using Canva AI image creation https://www.canva.com/ai-assistant/ is subject to the Canva Pro Content License.
References
Jhangiani, R. S., Chiang, I. A., Cuttler, C., & Leighton, D. C. (2019, August 1). Chapter 28: “Overview of non-experimental research“. Research Methods in Psychology. https://kpu.pressbooks.pub/psychmethods4e/chapter/overview-of-non-experimental-research/
Milgram, S. (1974). Obedience to authority: An experimental view. New York, NY: Harper & Row.
A research that lacks the manipulation of an independent variable.
Research that is non-experimental because it focuses on the statistical relationship between two variables but does not include the manipulation of an independent variable.
Research that is non-experimental because it focuses on recording systemic observations of behavior in a natural or laboratory setting without manipulating anything.