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J. Behav. Ther. & Exp. Psychiat. 41 (2010) 207–211

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Journal of Behavior Therapy andExperimental Psychiatry

journal homepage: www.elsevier .com/locate/ jbtep

Metacognitive training for patients with schizophrenia (MCT): Feasibility andpreliminary evidence for its efficacy

Julia Aghotor a,*, Ute Pfueller a, Steffen Moritz b,1, Matthias Weisbrod a,c,2, Daniela Roesch-Ely a

a University Hospital Heidelberg, Department of Psychiatry, Voßstr. 4, 69115 Heidelberg, Germanyb University Medical Center Hamburg-Eppendorf, Department of Psychiatry and Psychotherapy, Martinistr. 52, 20246 Hamburg, Germanyc SRH Klinikum Karlsbad – Langensteinbach, Department of Psychiatry, Guttmannstr. 1, 76307 Karlsbad, Germany

a r t i c l e i n f o

Article history:Received 1 July 2009Received in revised form21 December 2009Accepted 6 January 2010

Keywords:SchizophreniaTherapyMetacognitionPositive symptomsJumping to conclusions bias

* Corresponding author. Tel.: þ49 6221 56 38650;E-mail addresses: julia.aghotor@med.uni-heidelb

uke.uni-hamburg.de (S. Moritz).1 Tel.: þ49 40 42803 6565; fax: þ49 40 42803 7562 Tel.: þ49 7202 610; fax: þ49 7202 616161.

0005-7916/$ – see front matter � 2010 Elsevier Ltd.doi:10.1016/j.jbtep.2010.01.004

a b s t r a c t

Background: The treatment program ‘‘Metacognitive training for patients with schizophrenia’’ (MCT)addresses cognitive deficits and biases assumed to play a crucial role in the pathogenesis of delusions(e.g. jumping to conclusions, theory of mind deficits, bias against disconfirmatory evidence). The feasi-bility of this approach and its effects on positive symptoms and cognitive biases were investigated in thispilot study.Methods: Thirty inpatients of the Department of Psychiatry of the University Hospital Heidelberg witha schizophrenia spectrum diagnosis were randomly assigned to either MCT or an active control inter-vention. Both training programs were carried out over a time period of four weeks. Psychopathological,cognitive and metacognitive measures were collected at baseline and after completion of the training.Schizophrenia symptoms were determined blind to group allocation with the Positive and NegativeSyndrome Scale (PANSS).Results: No adverse reactions were noted in the MCT group and patients expressed a greater subjectivetraining success relative to the control condition (d ¼ .57). A stronger improvement on all PANSSsubscales was found at a descriptive level; positive symptoms attenuated under MCT with a mediumeffect size of d ¼ .43. In addition, results showed a reduced jumping to conclusions bias for MCT patients(d ¼ .31). However, none of the effects reached statistical significance. Optimal sample size was calcu-lated for future studies.Conclusion: The present study confirms the feasibility of MCT and provides preliminary evidence for itsefficacy ameliorating positive symptoms and the jumping to conclusions bias.

� 2010 Elsevier Ltd. All rights reserved.

1. Introduction

Psychological treatment of psychosis has long been neglectedand its application is the exception rather than the norm. However,in recent years, therapeutic approaches in the treatment ofschizophrenia – such as cognitive-behavioural therapy (CBT) – arebeginning to gain more ground. Derived from cognitive research oncognitive distortions and biases of schizophrenia, new approacheshave been developed for the treatment of schizophrenic disorders.Since the 1980s, a number of cognitive biases have been reported inschizophrenia that seem to be related to the formation andmaintenance of schizophrenia positive symptoms, particularly

fax: þ49 6221 56 5477.erg.de (J. Aghotor), moritz@

6.

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delusions. Among these biases or problematic thinking styles areattributional biases, the jumping to conclusions a bias (JTC), biasagainst disconfirmatory evidence, deficits in theory of mind, over-confidence in memory errors, and depressive cognitive patterns(for reviews see Bell, Halligan, & Ellis, 2006; Freeman, 2007; van derGaag, 2006; Moritz & T.S. Woodward, 2007).

The most well studied cognitive bias in psychosis is JTC. Severalstudies demonstrated evidence that persons with delusions jumpto conclusions on probabilistic reasoning tasks (Dudley, John,Young, & Over, 1997; Garety, Hemsley, & Wessely, 1991; Huq,Garety, & Hemsley, 1988; Lincoln et al., in press; Moritz &Woodward, 2005): they arrived at conclusions based on scarceevidence and often showed a high confidence level in theirdecisions.

According to Wykes (Wykes, Steel, Everitt, & Tarrier, 2008)evidence has accumulated over the last decade that CBT is efficientin the range of a weak to medium effect size in treating schizo-phrenic psychosis. Lincoln (2007) considers CBT in schizophrenia as

J. Aghotor et al. / J. Behav. Ther. & Exp. Psychiat. 41 (2010) 207–211208

a promising psychological intervention and calls for a need toaddress metacognitive problems of the disorder.

Unlike CBT which lies its focus on symptoms (frontdoorapproach), a new therapeutic training has been developed mainlytargeted at cognitive biases that subserve psychotic symptoms(backdoor approach): ‘‘Metacognitive training for patients withschizophrenia’’ – MCT (Moritz, Burlon, & Woodward, 2005; Moritz,Vizthum, Veckenstedt, Randjbar, & Woodward, in press; Moritz &T.S. Woodward, 2007). It aims at changing the ‘‘cognitive infra-structure’’ of delusional ideation by bringing metacognitiveimpairments to the attention of patients. Since psychosis does notbegin abruptly but is often preceded by a gradual change incognitive processes and the appraisal of the social environment,enhancing metacognitive competence may act prophylactically toprevent psychotic breakdown. The hope is that patients mayengage in further reasoning and challenge preliminary conclusionsthat previously would have been unequivocally accepted, and mayhave fostered delusional interpretations. In a recent study Rosset al. provided evidence that hasty decision-making is reduced bya brief reasoning training based on two MCT modules (Ross,Freeman, Dunn, & Garety, in press).

The objective of the following study was to examine the feasi-bility and efficacy of the MCT approach in patients with schizo-phrenia. The study aimed at evaluating benefits of the MCT forschizophrenia patients with regard to their ability to monitor andreconsider decision-making. It was examined to what extent theMCT leads to a reduction of positive symptoms (especially delu-sions) and to a greater reduction of the JTC bias compared to anactive control intervention.

2. Methods

Participants were recruited from the Centre for PsychosocialMedicine, Department of General Psychiatry of the University ofHeidelberg (Germany). The clinical trial was approved by the localEthics Committee and written informed consent was obtained fromall patients. Both study interventions were carried out in additionto the standard treatment.

2.1. Design

This study was performed as a Randomized Controlled ClinicalTrial (RCT). Patients were randomly allocated to either meta-cognitive training or an active control group (newspaper discussiongroup) according to a predetermined random plan (see Fig. 1). Thenon-stratified randomisation method was established by a certifiedstatician. Potential candidates were referred to us by ward physi-cians. Before intervention, psychopathological and neuro-psychological assessments - including cognitive and metacognitive

Fig. 1. Experimental flow chart.

variables – were carried out (baseline evaluation). Each patientthen participated in the training for a fixed period of four weeks.However, due to organizational reasons it was not possible to carryout the control intervention (once a week) as often as the MCT(twice a week). The newspaper discussion group was an establishedtreatment for inpatients and since artificially increasing the hoursof a control intervention has been shown to have an adverse effecton motivation (Hogarty et al., 2004; Velligan et al., 2000) the groupwas continued with the standard frequency. Neuropsychologicaland psychopathological data were re-evaluated after the trainingperiod (post assessment). Beforehand, trainers and raters receivedan extensive tutorial on the intervention and assessmentprocedures.

2.2. Sample

The main inclusion criterion for study participation was a diag-nosis of a schizophrenic spectrum disorder and patients shouldhave either previously experienced or be currently experiencingdelusions. Diagnoses relied on ICD-10 criteria (diagnoses F2.x) andwere made by experienced MDs prior to neurocognitive assess-ment. The age range was between 18 and 65 years. Patients witha history of severe neurological disorder as well as patientsshowing severe manifestations of hostility, megalomania, formalthought disorder and suspiciousness in the Positive and NegativeSyndrome Scale (PANSS) were not included (Kay, Fiszbein, & Opler,1987).

At the time of recruitment 57 inpatients fulfilled inclusioncriteria. 30 patients (20M/10 F; median age¼ 27 years, range 18–62years; median duration of illness ¼ 3.75 years, range .2–37.5 years)gave their consent for participation and completed the baselineassessment. However, three patients were excluded from furtheranalyses because of early discharge (no post assessment dataavailable). These outpatients were unable to complete the trainingand post assessment because of long distances between their homeand the study site. Another person was excluded because the initialdiagnosis was changed to a borderline personality disorder.

Experimental and control group did not significantly differconcerning age, gender, premorbid intelligence (assessed withMWT-B; Lehrl, 1999) and level of education. Patients’ demographiccharacteristics and symptoms at baseline are given in Table 1. In theMCT group 13 out of 16 patients did not miss more than one sessioncompared to 9 out of 14 patients in the active control intervention.

2.3. Metacognitive training

The MCT was designed as a group intervention program (3–10participants) consisting of eight sessions each lasting 45–60 min(the modules can be obtained cost-free and in several differentlanguages at www.uke.de/mkt).

The sessions aimed to bring cognitive distortions to theawareness of the patients and to prompt them to critically reflecton, complement and change their current repertoire of problem

Table 1Baseline characteristics of patients divided according to intervention.

n ¼ 30 MCT group x(SD; range)

Control group x(SD; range)

p

GenderMale/female 12/4 8/6 .56

Age(n ¼ 16/14) 28.9 (8.3; 18–48) 32.6 (12.1; 22–62) .13

MWT-B(n ¼ 16/14) 26.3 (6.2; 10–35) 28.9 (3.6; 23–33) .45

J. Aghotor et al. / J. Behav. Ther. & Exp. Psychiat. 41 (2010) 207–211 209

solving. Each module covered one of the following cognitive biases/metacognitive deficits displayed by patients with schizophrenia:dysfunctional attributional styles, JTC, theory of mind incorrigi-bility/lack of flexibility, need for closure, overconfidence in errorsand negative cognitive schemata.

In each module, patients were first familiarized with the targetdomain by everyday examples and illustrations. To emphasize therelevance of the modules for psychosis and to ensure a lastingimpact on patients, current scientific findings relating to the rela-tionship between the target domain and psychosis were conveyedseveral times in the course of each session. Leaflets with voluntaryhomework were handed out to the participants at the end of eachmodule to complement the program.

For example, two modules on JTC displayed visual materials thatoften prompt hasty decisions and induce false responses. In bothmodules, disadvantages of superficial inspection of informationand quick decisions were discussed in context of events related andunrelated to psychosis.

In another module dealing with overconfidence in errors,examples for common false memories were demonstrated andpatients were familiarized with factors that may impair memoryacquisition and distort recollection. Then, patients were showncomplex prototypical illustrations with typical elements removed(e.g. a beach scene without towels). In a recognition trial manypatients falsely remembered these lure items thus demonstratingthe constructive nature of memory. Subsequently, they were taughthow to differentiate between false and correct memories by the useof the so-called vividness heuristic.

2.4. Active control intervention (newspaper group)

For the control condition patients participated in a newspaperdiscussion group: They read articles on recent regional and politicalissues and discussed arising topics and questions. Furthermore,patients were asked to summarize the most important informationfrom article sections and voice their opinion on certain topics. Themain emphasis of the newspaper discussion group was aimed atimproving basic cognitive functions, such as working memory andselective attention. A further goal was to reduce speech blockageand communication difficulties and thereby foster social interac-tion skills.

2.5. Assessments

Psychopathological symptoms were rated with the Positive andNegative Syndrome Scale (Kay et al., 1987). Assessments wereperformed prior to and after the intervention by a trainedpsychologist or experienced MD who was blind to group allocationto avoid a rater bias.

Data on JTC were collected with the BADE procedure (Moritz &Woodward, 2006) which was administered as part of a larger testbattery. In this computer-based test procedure participants werepresented with three consecutive and ambiguous pieces of infor-mation about a situation. After presentation of each piece ofinformation, patients were requested to (re)rate the plausibility ofeither two or four causal interpretations on a 10-point scale. In

Table 2Results divided according to intervention.

n ¼ 30 MCT group x (SD; range)

Training satisfaction total (n ¼ 13/10) 37.9 (5.7; 27–49)

PANSS positive pre-post (n ¼ 14/12) 4.5 (4.8; 4–13)PANSS total pre-post (n ¼ 14/12) 17.1 (24.5; �27 to 44)JTC pre-post (n ¼ 12/11) 1.3 (2.3; 0–8)

addition to this rating, patients were asked after each informationwhether they would already decide for one interpretation. A deci-sion after only one sentence was judged as JTC. Compared to theconventionally used beads task, the BADE paradigm has theadvantage of containing multiple items and thus a continuous scorefor JTC. In a recent study (Moritz, Veckenstedt, et al., in press) wefound that the JTC parameter from the beads task and the BADEmapped onto the same factor speaking for the validity of the BADEJTC measure. In an upcoming dissertation we also obtainedevidence for a satisfactory re-test reliability of the BADE JTCmeasure in patients (Veckenstedt, in press).

Furthermore, a questionnaire evaluating subjective trainingsuccess was handed out to the patients at the end of the training.This subjective appraisal rating was previously used in a study onthe MCT (Moritz & T. Woodward, 2007), which found the internalconsistency to be satisfactory (Cronbach’s alpha ¼ .73). Themeasure contained 10 items covering distinct aspects of trainingsatisfaction: effectiveness, usefulness, applicability to daily life,transparency of the aims and fun. Each item had to be rated ona 5-point scale (1¼ does not agree at all – 5¼ totally agree). Higherscores thus designated greater satisfaction.

2.6. Data analysis

Group differences were calculated with a repeated-measuresANOVA with a significance level of p < .05, two-tailed. Further-more, effect sizes were calculated for between-group differences.Statistica Version 8.0 (StatSoft Inc, 2007) was used for the analyses.

3. Results

Patients expressed a greater subjective training success andsatisfaction under the MCT intervention compared to the activecontrol. Results did not achieve significance (F[1/21] ¼ 1.44; n.s.)but favoured MCT at a medium effect size of d ¼ .57 (see Table 2).Patients in this group also reported a higher willingness torecommend this training to others (p ¼ .07).

Patients in both groups were asked to comment on the trainingthey received: MCT patients were more willing to give feedback (14comments) than patients in the control intervention (7 comments):MCT patients positively commented on the numerous practicalexercises, interesting topics and vivid illustrations, especiallyregarding the modules on JTC, incorrigibility/lack of flexibility(module 3) and negative cognitive schemata (module 8). Patientsalso highlighted the pleasant atmosphere of the group interven-tion. Only the first five participants perceived the training as tooeasy and some tasks as unrealistic. Therefore, the training materialwas adjusted immediately concerning complexity, transparencyand transferability.

Besides training satisfaction, first results on psychopathologicaland metacognitive outcome measures were obtained. Results werenot significant; however, all PANSS subscales showed a greaterimprovement in patients allocated to MCT at a descriptive level. Inline with essential assumptions, MCT patients achieved betterresults after the training period: In comparison to the active controlgroup, the MCT yielded a higher efficacy for positive symptoms

Control group x (SD; range) p d

34.4 (6.3; 25–44) .18 .57

2.6 (4.1; �1 to 13) .29 .4311.9 (19.8; �13 to 53) .56 .2355 (2.7; �5 to 6) .46 .31

Fig. 3. Change of JTC bias (number of decisions after first information) under MCT andcontrol group between pre and post assessment.

J. Aghotor et al. / J. Behav. Ther. & Exp. Psychiat. 41 (2010) 207–211210

(PANSS Items 1–7) with a medium effect size (d ¼ .43; F[1/24] ¼ 1.18; n.s.; see Fig. 2) and for total symptoms with a smalleffect size (d ¼ .23; F[1/24] ¼ .34; n.s.).

Likewise, the BADE test procedure showed a non-significant, yetstronger reduction of the JTC bias for patients allocated to MCTrelative to the active control: Numeric values displayed morehesitant responses for MCT patients at the end of the treatmentwith predominantly small to medium effect sizes (d ¼ .31;F[1/21] ¼ .57; n.s.; see Fig. 3). Patients in the MCT group decidedless often for one of the given interpretations.

The reported effect sizes are preliminary, but provide tentativeevidence for the efficacy of the MCT and were used as a basis for thecalculation of an optimal sample size: Assuming an effect size ofd¼ .43 (present results), a beta (power) of .8 at an alpha-level of .05(two-tailed), a sample size of 86 in each group would be needed toachieve a significant effect.

No adverse reactions were noted in MCT attendants. Dropoutswere not linked to the training but to early discharge from the clinicor later change of diagnosis.

4. Discussions

The reported results are derived from a pilot study. This studyaimed at gaining experience with the MCT training and testing thefeasibility of this approach. The experience with the MCT trainingsessions revealed a good acceptance of the interactive presentationand an active involvement by the patients. The adjustments of thetraining materials concerning complexity, transparency andtransferability had a positive impact on adherence and were laterincorporated into the manual (available cost-free at www.uke.de/mkt). A number of patients who fulfilled inclusion criteria werenot able to participate due to interference with other clinicaltreatment. Attendance of participating patients was good, however.

At a medium effect size, MCT led to a greater improvement ofpositive symptoms than the active control intervention. Severalreasons need to be considered why we failed to find significanceeffects:

The material was optimized concerning transparency andcomprehensibility over the course of the trial, which might haveinfluenced findings, especially for the first attendants who foundsome of the material too easy and may have not achieved optimaltraining success. Further studies need to clarify, whether thetraining adjustments and the currently available manual might

Fig. 2. Change of positive Symptoms (PANSS Positive Scale) under MCT and controlgroup between pre and post assessment.

improve the effectiveness of the training and training satisfaction.Several trials speak for this possibility (Moritz & T. Woodward,2007), including a recently completed trial with the two moduleson JTC in a British study (Ross et al., in press). Further, althoughmetacognitive awareness was no explicit aim of the newspapergroup, discussions of articles and exchange between patients mayhave partially fostered social cognition and improved decision-making. Therefore, results may have emerged even stronger witha treatment as usual or wait list group.

We would also like to mention the following shortcomings ofthe trial and suggestions for further studies: The results reportedare drawn from a feasibility study with only thirty inpatients withschizophrenia. Therefore, effects should be tested in a studyproviding optimal sample size. Future studies would also benefitfrom determining a clinically significant change on the primaryoutcome measures, using the Reliable Change Index (RCI).

Moreover, no conclusion can be made concerning stability ofeffects in the long-term since no follow-up data were collected upto this point and the intervention period of four weeks was rathershort which might have limited learning effects. We already listedreasons for different training conditions of both groups; however,further studies need to provide matched conditions concerningtime and treatment intensity for both groups to eliminatea potential bias.

The PANSS still represents the gold standard for the assessmentof schizophrenia symptoms in clinical and research settings (Bell,Milstein, Beam-Goulet, Lysaker, & Cicchetti, 1992; Muller et al.,1998). While the conventinal three subscale algorithm was adoptedhere, several studies (Emsley, Rabinowitz, & Torreman, 2003;Lindenmayer, Grochowski, & Hyman, 1995), favour a five-factorsolution (negative, positive, disorganised [or cognitive], excitedand depression/anxiety factors). In addition, the psychopatholog-ical assessment should be complemented by a standardized diag-nostic instrument, e.g. a structured clinical interview for psychiatricdisorders. Further studies would benefit from these considerationsand the complementation with other assessment scales, such as thePsychotic Symptom Rating Scales (PSYRATS; Haddock, McCarron,Tarrier, & Faragher, 1999), which covers important aspects ofdelusions not captured by the PANSS, such as delusional conviction.

This study was mainly aimed at investigating feasibility andpracticability. Analysis of metacognitive data was thereforerestricted to the most well studied cognitive bias JTC. Future studiesshould thus target other biases and deficits.

J. Aghotor et al. / J. Behav. Ther. & Exp. Psychiat. 41 (2010) 207–211 211

5. Conclusions

The training implementation and the results indicate that MCT isa safe and feasible intervention for schizophrenia. Even though dataand results were not fully conclusive, the calculated effect sizes werenonetheless promising and point at a reduction of positive symptoms,JTC bias, and a good acceptance of the MCT by patients. Reportedshortcomings are addressed in a clinical trial currently in progress.

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