Exam 14: Selecting a Research Design for a Group Evaluation Study

The length of time the client has experienced the target behavior is an important determinant of whether we should consider maturation a threat to internal validity that should be of special concern.

If a client has experienced the target behavior for more than a year, history should be considered a major threat to internal validity.

Illustrate how you might evaluate your own practice using a group research design by answering each of the following questions: (1) What is the target behavior that you will measure? (2) What research design will you employ? (3) What threats to internal validity do you believe should be of special concern in this situation, and why do you believe this threat should be of special concern? (4) Does your chosen research design control for the threats of special concern (If there are no threats, just say so as your answer to this question)?

The posttest-only control group research design controls for maturation and history as threats to internal validity.

When you employ an experimental research design, you ______.

The comparison group design is better than the one-group pretest-posttest design at controlling for maturation as a threat to internal validity because the gain on the measured behavior for the comparison group is an indicator of the effect of normal growth over time.

Statistical regression as threat to internal validity refers to the fact that extreme scores for a scale (i.e., very high or very low scores) tend naturally to move toward the mean with repeated measurements; thus, it would not make sense to take only the clients with the extremely low pretest scores as your clients for an evaluation study and employ the one-group pretest-posttest design.

When you fail to view your evaluation of practice as having any of the common threats to internal validity, you do not need to discuss this in your report of your study.

The main reason we need to know the research design employed in an evaluative study is that we will be in a better position to determine whether ______.

Maturation, as a threat to internal validity, refers to ______.

The research design that you employ in an evaluative study will reveal the ______.

Which of the following does the best job of controlling for threats to internal validity?

A group research design is only used when your clients are being given a group treatment (e.g., a support group); it is not appropriate for a group of clients being treated individually for a given target behavior using a common measurement tool.

A threat to internal validity refers to ______.

Answer the following four questions: (1) What is maturation as a threat to internal validity? (2) What is history as a threat? (3) Does the one-group pretest-posttest research design control for maturation as a threat to internal validity? (4) Explain why or how your answer to Question 3 is true or false.