This paper defines correlational vs experimental research types and highlights the difference between correlational and experimental research designs. It includes advantages, disadvantages, and examples.
Introduction
In psychology, there are two predominant types of research – correlational study vs experiment. Although they share certain similarities, it is very important to understand that these types of research are not the same thing. It is also important to be able to differentiate between the two, as the confusion might result in wrongful interpretations of research designs and their methods. The purpose of this paper is to give clear definitions of what correlational and experimental types of research are, compare them, and highlight the differences between experimental vs correlational study.
Correlational Research
Correlational research is highly widespread not only in psychology but also in other sciences. It helps measure the association between different variables without interfering with the process. In many ways, it is considered to be observational research, where scientists are taking into account all of the variables and try to figure out if there is a connection between them. Correlational research, in many cases, helps identify all of the possible variables before anything else could be done about them.
Correlations can be positive and negative. Positive correlations stand for positive associations between different variables – if one of them is increased, the other ones see an increase also (McLeod, “Correlation”). Negative correlations, on the other hand, work differently. Should one variable see a decrease while the other is being increased, it would then reveal a negative correlation. The discovery of low levels of neurotransmitters, such as serotonin and norepinephrine in patients diagnosed with clinical depression, can be considered an example of correlational research. While this research managed to identify and measure a variable, it did not necessarily establish a cause-effect relationship between clinical depression and low levels of serotonin and norepinephrine (McLeod, “Correlation”).
Correlational experiments are used for prediction, testing the validity and reliability of the results, and theory verification (predictive validity). They are good for testing naturally occurring variables. The results of correlations are typically easy to understand and illustrate in graphic form (McLeod, “Correlation”).
Experimental Research
This type of research is, perhaps, the most popular one in medicine, as the results of randomized control trials (which are experiments) are held in the highest regard by medical specialists and the evidence extracted via an experiment is considered top-tier, provided that the premise and the execution of the experiment lacked any flaws. Naturally, experimental research is popular in psychology, which is considered a field of medicine.
Experimental research isolates and manipulates certain variables in order to see how other variables are affected (McLeod, “Experimental Method”). Experimental research exists to establish cause-and-effect connections between them (McLeod, “Experimental Method”). That is why the experiment is very useful for testing out various hypotheses. During an experiment, the environment is strictly controlled in order to eliminate the effects of other independent variables, as that would obscure the picture. An example of the experimental method would be the Milgram Experiment, which tested the relationship between authority and obedience (McLeod, “Experimental Method”).
There are several types of experiments, the most common ones being laboratory experiments, field experiments, and natural experiments. The strength of any experimental method typically lies in its high accuracy. However, the results of an experiment cannot be considered 100% accurate due to the fact that laboratory experiments have a chance of distorting naturally-occurring processes and variables, while natural and field experiments could have variables which were unaccounted for, thus producing bias and distorting the data and the conclusions based on said data (McLeod, “Experimental Method”).
The Main Difference between Correlational and Experimental Research
Aside from obvious differences in types of experimental and correlational researchers, as well as various small deviations one from another, the main difference between these two types of research is in the fact that correlation is not and cannot imply causation (“Difference”).
Even if there are very strong suggestions about certain variables being connected to others, under the scope of correlational research, we cannot make that conclusion. An experiment is the type of research to determine cause-and-effect, while correlational research can merely describe the relationship between the two variables. It cannot imply that one variable causes the other, as these variables are not isolated from the rest of the system, thus meaning that the cause-and-effect may be caused by a different variable that was not the scope of the study (“Difference”).
A correlational study could, sometimes, be the only way to study a naturally-occurring phenomenon, should an experiment be, under certain circumstances, impossible or unethical. For example, it would be unethical to conduct an experiment on lung cancer by asking the participants to smoke cigarettes (“Difference”).
Conclusions
Correlational studies focus on studying the variables in a mostly natural setting, identifying them, and establishing relationships between them. However, these relationships cannot imply that there is a cause-and-effect connection between either of these variables. Experiments single out certain independent variables and influence them to determine cause-and-effect between them and dependent variables. That is the main difference between correlational and experimental studies. Each has its uses, depending on the circumstances and the scope of every individual research.
Works Cited
“Difference between correlational and experimental research.” Difference Between. 2012. Web.
McLeod, Saul. “Correlation.” Simply Psychology, 2008. Web.
—. “Experimental method.” Simply Psychology, 2012. Web.