The Effects of Mindfulness-Based Therapy on Anxiety and Depression: A Meta-Analytic Review

The Journal of Consulting and Clinical Psychology recently published a meta-analysis by Dr. Stefan Hoffman and colleagues at Boston University on mindfulness-based therapies for anxiety and depression.

For those of you who don’t know, a meta-analysis is an analysis of a collection of research studies. Researchers calculate what are called effect sizes for the studies. This allows researchers to amalgamate several studies in order to test research hypotheses.

After conducting a thorough literature review, the researchers found 39 studies that met their criteria. The vast majority of these were studies of Mindfulness-Based Stress Reduction (MBSR) and Mindfulness-Based Cognitive Therapy (MBCT).

From the results, the researchers conclude that mindfulness-based treatments appear to be effective in treating anxiety and depression. Additionally, the researchers note that mindfulness-based treatment may have a general applicability in addressing different processes across a wide range of conditions, severity, and in association with other problems such as medical conditions (e.g., cancer).

At the end of the study, the authors state their personal biases about the outcomes they expected. They admit that they were skeptical of mindfulness-based therapies and expected to find very small, if not nonsignificant effects. In fact, Dr. Hofmann co-authored a paper a few years ago that was critical of mindfulness-based treatment, titled, “Acceptance and Mindfulness-Based Therapy: New Wave or Old Hat?” For these reasons, I think this article is an inspiring example of the integrity of the scientific method and the researchers who adhere to it. Despite their biases, Hofmann and colleagues were willing to move where the data led them. They did not try to explain away results that contradicted their expectations; instead, they conclude in the abstract that mindfulness-based therapy is a “promising intervention” for treating anxiety and depression.

For ACBS members, you can download the paper at their website. (UPDATE: Download an NIH copy of the article for free here.)

The full citation:

Hofmann, S. G., Sawyer, A. T., Witt, A. A., & Oh, D. (2010). The effect of mindfulness-based therapy on anxiety and depression: A meta-analytic review. Journal of Consulting and Clinical Psychology, 78(2), 169-183.