Metacognitive training (MCT) for patients with psychosis is a psychological group intervention that aims to educate patients about common cognitive biases underlying delusion formation and maintenance, and to highlight their negative consequences in daily functioning.

In this randomized controlled trial, 154 schizophrenia spectrum patients with delusions were randomly assigned to either MCT + treatment as usual (TAU) or TAU alone. Both groups were assessed at baseline, and again after 8 and 24 weeks. The trial was completed fully by 111 patients. Efficacy was measured with the Psychotic Symptom Rating Scales (PSYRATS) Delusions Rating Scale (DRS), and with specific secondary measures referring to persecutory ideas and ideas of social reference (the Green Paranoid Thoughts Scale, GPTS), cognitive insight (the Beck Cognitive Insight Scale, BCIS), subjective experiences of cognitive biases (the Davos Assessment of Cognitive Biases Scale, DACOBS) and metacognitive beliefs (the 30-item Metacognitions Questionnaire, MCQ-30). Economic analysis focused on the balance between societal costs and health outcomes (quality-adjusted life years, QALYs).

Both conditions showed a decrease of delusions. MCT was not more efficacious in terms of reducing delusions, nor did it change subjective paranoid thinking and ideas of social reference, cognitive insight or subjective experience of cognitive biases and metacognitive beliefs. The results of the economic analysis were not in favour of MCT + TAU.

In the present study, MCT did not affect delusion scores and self-reported cognitive insight, or subjective experience of cognitive biases and metacognitive beliefs. MCT was not cost-effective.

Although antipsychotic medication still represents the treatment of choice for schizophrenia, its objective impact on symptoms is only in the medium-effect size range and at least 50% of patients discontinue medication in the course of treatment. Hence, clinical researchers are intensively looking for complementary therapeutic options. Metacognitive training for schizophrenia patients (MCT) is a group intervention that seeks to sharpen the awareness of schizophrenia patients on cognitive biases (e.g. jumping to conclusions) that seem to underlie delusion formation and maintenance. The present trial combined group MCT with an individualized cognitive-behavioural therapy-oriented approach entitled individualized metacognitive therapy for psychosis (MCT+) and compared it against an active control.

A total of 48 patients fulfilling criteria of schizophrenia were randomly allocated to either MCT+ or cognitive remediation (clinical trial NCT01029067). Blind to intervention, both groups were assessed at baseline and 4 weeks later. Psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS) and the Psychotic Symptom Rating Scales (PSYRATS). Jumping to conclusions was measured using a variant of the beads task.

PANSS delusion severity declined significantly in the combined MCT treatment compared with the control condition. PSYRATS delusion conviction as well as jumping to conclusions showed significantly greater improvement in the MCT group. In line with prior studies, treatment adherence and subjective efficacy was excellent for the MCT.

The results suggest that the combination of a cognition-oriented and a symptom-oriented approach ameliorate psychotic symptoms and cognitive biases and represents a promising complementary treatment for schizophrenia.