You can reduce the disadvantages of a between subjects design by increasing the statistical variance.

Question

Quizplus · Accepted Answer

Increasing the statistical variance can actually make the disadvantages of a between subjects design worse, as it can increase error variance and decrease power. To reduce the disadvantages of a between subjects design, other methods such as random assignment, matching, or within subjects designs may be more effective.

You Can Reduce the Disadvantages of a Between Subjects Design