What is the evidence for the efficacy of self-help acceptance and commitment therapy? A systematic review and meta-analysis

Acceptance and Commitment Therapy (ACT) is a form of psychotherapy with growing evidence for its transdiagnostic effects. Traditionally face-to-face, ACT is also delivered in self-help formats. As self-help is becoming more prevalent, the demand for empirical evidence of the efficacy of ACT self-help is increasing, and there are concerns that intervention outcomes are being ‘over-sold’. A systematic search of the literature was conducted to find all peer-reviewed randomized controlled trials investigating the efficacy of ACT self-help on depression, anxiety, and/or psychological flexibility (PF). Thirteen studies were identified and reviewed, totaling 2580 participants. A quality appraisal of the papers under review indicated bias in methodology and reporting that may be limit the interpretability of existing evidence. Meta-analysis showed significant small effect sizes favoring intervention for depression (g=0.34; 95% CIs [0.07, 0.61]; Z=2.49, p=.01), anxiety (g=0.35; 95% CIs [0.09, 0.60]; Z=2.66, p=.008), and PF (g=0.42; 95% CIs [0.14, 0.70]; Z=2.93, p=.003) outcomes. Results indicate that higher levels of clinician guidance improves outcomes but that intervention format (e.g. book/computer) is unlikely to moderate results. Analysis also showed that increases in PF were associated with reductions in depression (rho=−.70, p=.25, n=10) and anxiety (rho=−.90, p<.001, n=10), giving initial support for the theory that changes in PF mediate distress outcomes. Therefore, ACT self-help may be a suitable intervention, particularly when clinician guidance is given. However, due to the small effect sizes, limited number of studies, and considerable heterogeneity of results, any conclusions made are tentative.

To find the full text version of this article and others (as well as download a full text .pdf.), ACBS members can visit the ScienceDirect homepage here.