Correlational Methods are a form of research that include “quasi-experimental” designs such as survey research or naturalistic observations, in which different groups are compared, but cause and effect between variables cannot be determined. These are different from True Experimental Designs because there is no control condition, nothing is manipulated, and there are many differences between the groups other than the independent variable(s).
However, correlational studies are often easier to conduct than experiments and can be used when conducting a controlled experiment is impossible. For example, if we wanted to examine the relationship between grade point average and number of alcoholic drinks per week, we cannot ethically assign participants to binge-drinking conditions. We can only observe drinking behavior in a real-world setting or rely on participants’ self-report.