What is the most serious threat to internal validity in nonequivalent control group design?
A) selection
B) maturation
C) mortality
D) testing

Question

Quizplus · Accepted Answer

The most serious threat to internal validity in nonequivalent control group design is selection, which is the unequal assignment of individuals to the treatment and control groups. This can result in pre-existing differences between the groups that affect the outcomes of the study. Maturation, mortality, and testing can also pose threats to internal validity, but they are not as significant as selection.

What Is the Most Serious Threat to Internal Validity in Nonequivalent