Mindfulness-based cognitive therapy (MBCT) appears to be a promising intervention for the prevention of relapse in major depressive disorder, but its efficacy in patients with current depressive symptoms is less clear. Randomized clinical trials of MBCT for adult patients with current depressive symptoms were included (k = 13, N = 1046). Comparison conditions were coded based on whether they were intended to be therapeutic (specific active controls) or not (non-specific controls). MBCT was superior to non-specific controls at post-treatment (k = 10, d = 0.71, 95% confidence interval [CI] [0.47, 0.96]), although not at longest follow-up (k = 2, d = 1.47, [-0.71, 3.65], mean follow-up = 5.70 months across all studies with follow-up). MBCT did not differ from other active therapies at post-treatment (k = 6, d = 0.002, [-0.43, 0.44]) and longest follow-up (k = 4, d = 0.26, [-0.24, 0.75]). There was some evidence that studies with higher methodological quality showed smaller effects at post-treatment, but no evidence that effects varied by inclusion criterion. The impact of publication bias appeared minimal. MBCT seems to be efficacious for samples with current depressive symptoms at post-treatment, although a limited number of studies tested the long-term effects of this therapy.
Keywords: Mindfulness-based cognitive therapy; depression; meta-analysis; relative efficacy.