What is the difference between dependent variables, independent variables, control variables, and confounding variables?

A variable is something that can take on different values. A study contains independent and dependent variables, control variables, and confounding variables that influence its results.

Dependent variables represent the outcome of a study. Researchers measure how they change under different values of the independent variable(s).

Independent variables are manipulated by the researcher to observe their effect on dependent variables.

Control variables are variables that are held constant to isolate the effect of the independent variable.

Confounding variables are variables that have not been controlled for that may influence a study’s results.

The expected relationship between these variables can be illustrated using a conceptual framework.