Common factors in psychotherapy outcome: Meta-analytic findings and their implications for practice and research

It is often reported in meta-analytic studies of adult psychotherapy that psychotherapy produces positive change but that there are few significant differences between different types of psychotherapy. Because meta-analyses indicate more similarities than differences among therapies, the "active ingredients" of therapy appear to include important factors in addition to specific therapeutic techniques. Research on common factors across therapies has existed for more than 60 years but is rarely mentioned in the social work literature. Common factors include the client and the client's context, the therapeutic relationship, and expectancy. These studies support the worth of the efforts of social work practitioners, suggest avenues for future research, and have implications for policy and education. The author of this article describes relevant meta-analytic studies of adult psychotherapy, examines the common factors perspective on psychotherapy efficacy, and sets forth implications for social work.