Researchers interested in evaluating the outcomes of psychotherapy distinguish between effectiveness and efficacy research. In contrast to effectiveness research, efficacy research:
- has better internal validity but limited external validity.
- has limited internal validity but better external validity.
- has better internal and external validity.
- has limited internal and external validity.
The Correct Answer is A.
Efficacy studies are conducted in well-controlled conditions, often using a structured manualized session format. In contrast, effectiveness studies are conducted in real-world settings with less experimental control. Therefore, while efficacy studies are useful for determining whether a treatment has beneficial effects under controlled conditions, effectiveness studies are useful for determining if those effects generalize to other conditions.
(Note that, to identify the correct answer to this question, you not only have to be familiar with efficacy and effectiveness research but also with internal and external validity, which are described in the Statistics and Research Design chapter of the written study materials.)
Answer B: A criticism of efficacy research is that, by controlling many of the crucial elements of what is actually done during the course of delivering psychotherapy, the results have good internal validity but limited external validity.
Answer C: Efficacy studies are deemed to have good internal validity but limited external validity.
Answer D: Efficacy studies are deemed to have good internal validity but limited external validity.