What is a confounding variable?

confounding variable is a variable that hides the true effect of another variable in your experiment. It is often closely related to your independent variable.

For example, in an experiment about the effect of salt addition on plant health, confounding variables could include pot size and soil type, which might affect plant health as much as or more than salt addition. These variables need to be held constant to allow you to measure the true effect of the variable you are interested in.

In your experimental design, it’s important to identify potential confounding variables and plan how you will control for them.