In experimental research, what is manipulated to measure its effects?

In experimental research, the independent variable is the factor that the researcher intentionally manipulates to observe its effects on another variable, known as the dependent variable. This manipulation is crucial because it allows researchers to establish cause-and-effect relationships between variables.

For example, if a study aims to determine how different doses of a medication affect patient recovery times, the doses of the medication would be the independent variables manipulated by the researcher. By changing this variable and observing the corresponding changes in recovery times, which are measured as dependent variables, the research can draw conclusions about the impact of the different doses on recovery.

Control variables, on the other hand, are kept constant to prevent them from influencing the results, while random variables may refer to variations in uncontrollable factors that can affect the outcome but are not the focus of the study. Understanding the role of the independent variable is essential for designing effective experiments and interpreting data accurately.