In a within-subjects research study, factors that change over time, such as history and maturation, can be threats to ____.
A) internal validity only
B) external validity only
C) both internal and external validity
D) neither internal nor external validity

Question

Quizplus · Accepted Answer

Factors like history and maturation that change over time in a within-subjects study primarily threaten internal validity because they can influence the outcomes of the study, making it difficult to attribute changes in the dependent variable directly to the manipulation of the independent variable.

In a Within-Subjects Research Study, Factors That Change Over Time