Effectiveness of metacognitive interventions for mental disorders in adults—A systematic review and meta‐analysis (METACOG)

Abstract

We evaluated the effectiveness and acceptability of metacognitive interventions for mental disorders. We searched electronic databases and included randomized and nonrandomized controlled trials comparing metacognitive interventions with other treatments in adults with mental disorders. Primary effectiveness and acceptability outcomes were symptom severity and dropout, respectively. We performed random‐effects meta‐analyses. We identified Metacognitive Training (MCTrain), Metacognitive Therapy (MCTherap), and Metacognition Reflection and Insight Therapy (MERIT). We included 49 trials with 2,609 patients. In patients with schizophrenia, MCTrain was more effective than a psychological treatment (cognitive remediation, SMD = −0.39). It bordered significance when compared with standard or other psychological treatments. In a post hoc analysis, across all studies, the pooled effect was significant (SMD = −0.31). MCTrain was more effective than standard treatment in patients with obsessive–compulsive disorder (SMD = −0.40). MCTherap was more effective than a waitlist in patients with depression (SMD = −2.80), posttraumatic stress disorder (SMD = −2.36), and psychological treatments (cognitive–behavioural) in patients with anxiety (SMD = −0.46). In patients with depression, MCTherap was not superior to psychological treatment (cognitive–behavioural). For MERIT, the database was too small to allow solid conclusions. Acceptability of metacognitive interventions among patients was high on average. Methodological quality was mostly unclear or moderate. Metacognitive interventions are likely to be effective in alleviating symptom severity in mental disorders. Although their add‐on value against existing psychological interventions awaits to be established, potential advantages are their low threshold and economy.

Insight and psychosis: the next 30 years

“…Talking therapies designed to improve metacognition (metacognitive therapy and metacognitive training) across a range of mental disorders have been developed and tested in small clinical trials. A systematic review 17 found 19 controlled studies in schizophrenia, of which 15 were randomised. The results approached significance when compared with standard or other psychological treatments, with a pooled standard mean difference in positive symptoms scores estimated to be −0.31 (95% CIs −0.50 to −0.12).…”

Study protocol of a randomised clinical trial testing whether metacognitive training can improve insight and clinical outcomes in schizophrenia

“…This is the first large RCT testing the long-term effects of group MCT on clinical and cognitive insight in addition to several relevant clinical outcomes in a representative sample of patients with schizophrenia spectrum disorders. Although MCT has been consistently demonstrated to improve positive symptoms [14][15][16][17][18], the benefits of MCT on insight are yet to be established [3], which is of major clinical relevance given the association of insight with outcomes in schizophrenia and related disorders [2]. This is supported further by three previous trials which revealed other non-MCT metacognitively oriented treatments to have a positive impact on insight [20][21][22].…”

“…Under these assumptions, for reaching a sufficient statistical power of β = 80% at the end of the study, we will need n = 63 subjects in each arm, that is, a total sample size of N = 126 patients, who will be analysed at the end of the study on an intention-to-treat (ITT) basis. Attrition rates in previous RCTs investigating MCT effects on symptoms were low (approximately 10%) [18]. However, since we will follow-up patients over a more prolonged period (1 year) we have conservatively assumed a much higher drop-out rate of 50%.…”

“…In addition to the primary outcome of this RCT, namely insight, we will consider several clinical outcomes, both positive and negative, such as symptom severity, functioning, readmissions and suicidal behaviour, thus testing the so-called 'Insight Paradox' [54]. Although the positive impact of MCT on symptoms has been established [14][15][16][17][18], most of previous RCTs included in these meta-analyses compared MCT with TAU. Therefore, not only this RCT may replicate this, but also by comparing the MCT group with an active intervention control group, if the above positive effect was shown, this would provide further support for the benefits of MCT on symptoms.…”

“…MCT was first developed by Steffen Moritz and Todd Woodward [13] and is available at no cost at: http:// www.uke.de/mct. Since then, one systematic review [14] and four meta-analyses [15][16][17][18] have replicated the positive effects of MCT on positive symptoms, particularly delusions, when compared with 'treatment as usual' (TAU), although one meta-analysis [19] failed to show such an association. However, to the best of our knowledge no definitive randomised clinical trial (RCT) using MCT has considered insight as primary outcome to date, although three previous RCTs found other non-MCT metacognitively oriented therapies to improve insight in first-episode psychosis [20] and schizophrenia [21,22].…”