An ABAB design has internal validity advantages over the ABA designGroup of answer choicesFalseTrue

True. An ABAB design does have internal validity advantages over the ABA design.

Here's why:

1. In an ABA design, the subject is observed in a baseline condition (A), then in a treatment condition (B), and then again in the baseline condition (A). This design allows for the examination of what happens when the treatment is removed.

2. However, the ABAB design, also known as a reversal design, extends the ABA design by adding another treatment phase (B). This means the subject is observed in the baseline condition (A), then in the treatment condition (B), then back to the baseline (A), and then in the treatment condition again (B).

3. The advantage of the ABAB design is that it allows for the verification of the effects of the treatment. If the subject's behavior changes with the introduction and removal of the treatment, and then changes again when the treatment is reintroduced, it provides stronger evidence that the treatment, and not some other factor, is causing the change in behavior.

4. Therefore, the ABAB design has greater internal validity because it provides a better test of whether the treatment is causing the observed changes.