Abstract
Much of the burden associated with poor mental health is associated with symptom experience in the general population. We conducted a systematic review and meta-analysis of studies conducted in nonclinical samples, evaluating mindfulness-based programs (MBPs) for outcomes related to psychological health and well- being. We focused on mindfulness-based stress reduction (MBSR) and mindfulness-based cognitive therapy (MBCT) because they have the strongest evidence base. We searched MEDLINE, PsycINFO, EMBASE, and CINAHL (from 2006 to February 2019) for published peer-reviewed journals articles of intervention studies evaluating MBCT or MBSR for psychological health and well-being in nonclinical samples. Data were pooled using a random-effects model, and effect estimates were reported as Hedges' g. We included 49 studies conducted in nonclinical samples (n = 4,733). When compared with a passive control, MBPs significantly reduced symptoms of rumination/ worry (g = -1.13, [-2.17, -0.08]), stress/psychological distress (g = -0.52 [-0.68, -0.36]), depression (g = -0.45 [-0.64, -0.26]), and anxiety (g = -0.44 [-0.65, -0.23]), and significantly improved quality of life/well-being (g = 0.32 [0.10, 0.54]). In general, MBCT generated larger effect sizes than MBSR for all outcomes. This study provides evidence that in nonclinical samples, MBPs are associated with benefits to health and well-being. These findings add to the growing evidence base suggesting that MBSR and MBCT may be effective approaches for subclinical levels of mental ill-health and could form part of the public mental health agenda.