Efficacy of systemic therapy on adults with mental disorders: A meta-analysis

To evaluate the efficacy of systemic therapy on psychiatric disorders in adulthood.

This meta-analysis integrates results of 37 randomized controlled trials (RCT) of therapy with an explicit systemic focus on adults with psychiatric disorders. Studies were identified through systematic searches in electronic databases and cross-referencing.

On average, systemic therapy had stronger short-term (g = .51) and long-term (g = .55) efficacies than control groups without alternative treatment and stronger short-term effects than alternative active treatments (g = .25). In addition, efficacy of systemic therapy was similar to those of other bona fide psychotherapies. Individuals receiving systemic therapy plus medication showed stronger improvements at posttest (g = .71) and follow-up (g = .87) than those receiving only medication. Illness-specific analyses showed positive short-term efficacy of systemic therapy on eating disorders, mood disorders, obsessive-compulsive disorders, schizophrenia, and somatoform disorders. At follow-up, efficacy of systemic therapy was only found on eating disorders, mood disorders, and schizophrenia. In addition, systemic therapy had lower dropout rates than alternative treatments. For certain comparisons, effect sizes were moderated by participant age, study quality, and year of publication.

We conclude that the present meta-analysis found some evidence for the efficacy of systemic therapy on five disorders, but the number of available RCT is still limited. More research is needed on systemic therapy of other disorders, such as anxiety disorders and substance use disorders.