ABSTRACT
Metacognitive therapy (MCT) aims to modify dysfunctional metacognitions that are thought to be universal determinants of emotional distress and psychological dysfunction more generally. MCT is an effective treatment for emotional distress symptoms, but less is known about its effect for other types of psychological problems. Interpersonal problems are common in psychological disorders and should be improved following psychotherapy. Therefore, we conducted a systematic review and meta-analysis of trials on the effects associated with MCT for interpersonal problems among adults with mental health disorders published until 15 November 2023 using PubMed, Cochrane Library and PsycNet. Trials with a minimum of 10 participants were included. A total of six studies based on five trials reported on the effectiveness of MCT for interpersonal problems and met our inclusion criteria. Two trials evaluated MCT for patients with major depressive disorders, two for patients with anxiety disorders and one for borderline personality disorder. Three of the trials were randomized controlled trials. Four of the trials reported follow-up data but varied in their time-points. The within-group effect size estimate from pretreatment to posttreatment across five trials was large (g = 0.865, 95% CI [0.512–1.218]). Our results indicate that MCT is an effective treatment for improving interpersonal problems in individuals with common mental disorders, even though the treatment is short and primarily concern improving mental regulation through modifying metacognitions. While this finding is in line with metacognitive theory, more trials evaluating personality and interpersonal functioning are needed to draw firm conclusions.