Holding a participant variable constant has the double advantage of (1) preventing the variable from becoming a confounding variable, and (2) reducing variance within groups. True or False

The provided statement is True.

Step-by-step explanation:

Holding a variable constant implies that there are no kind of relationship between the variables and the treatments.

Holding a participant variable constant has the double advantage:

(1) preventing the variable from becoming a confounding variable

(2) reducing variance within groups.

A confounding variable effects both the dependent and the independent variable remarking a relationship between the two.

Variation within group implies the difference caused by the individual values of each group.

Thus, the provided statement is True.