Possible problems with the one group pretest-posttest design include:
A) Maturation effects
B) Carryover effects
C) Ecological validity
D) a and b

Question

Quizplus · Accepted Answer

This is because the one group pretest-posttest design lacks a control group, which makes it difficult to determine whether changes in the dependent variable were due to the intervention or to other factors such as maturation or carryover effects. Maturation effects refer to changes that occur over time because of normal developmental processes, while carryover effects occur when the treatment in one phase of the study affects the outcome in a subsequent phase. Ecological validity refers to the extent to which the findings of the study can be generalized to real-world settings, which is not directly related to the issues with a one group pretest-posttest design.

Possible Problems with the One Group Pretest-Posttest Design Include