Effects of history are ______ to occur in pretest-posttest designs.
A) least likely
B) most likely
C) unlikely
D) not known

Question

Quizplus · Accepted Answer

Pretest-posttest designs are vulnerable to the effects of history, as changes in the outcome of interest between the pretest and posttest may be due to external events or other historical factors, rather than the intervention being studied. This is especially true in longer-term studies or those conducted in naturalistic settings where many events may occur over time. Therefore, it is most likely that effects of history will occur in pretest-posttest designs.

Effects of History Are ______ to Occur in Pretest-Posttest Designs