Schizophrenia is a very disabling mental disorder, with a usual onset in late adolescence or early adulthood and a lifetime prevalence of 0.5–1% (McGrath, Saha, Chant, & Welham, 2008). Schizophrenia covers a diverse group of individuals, suffering from a wide range of symptoms (Tandon, Nasrallah, & Keshavan, 2009). A Diagnostic and Statistical Manual of Mental Disorders-IV-Text Revision (DSM-IV-TR) diagnosis of schizophrenia is based on the presence of two out of five specific positive symptoms: delusions, hallucinations, disorganized speech, disorganized/catatonic behavior and negative symptoms (e.g., affective flattening, avolition and anhedonia). Social or occupational dysfunction and a measure of duration are taken into account as well (American Psychiatric Association, 2000).

Besides these characteristic symptoms, deficits in metacognitive abilities are also common in people with schizophrenia (Lysaker et al., 2005). Metacognition was first described by Flavell (1979) as the ability to reflect upon one’s own thinking and to observe and detect errors in one’s cognitive processes. While metacognition as a singular continuum is intuitively appealing, Semerari et al. (2003) propose that metacognition is modular in nature, with different aspects of metacognition originating from different sources and leading to different outcomes. The comprehensive definition of Lysaker, Dimaggio, Buck, Carcione, and Nicolò (2007; based on Semerari et al., 2003) combines several modular aspects of metacognition: understanding one’s own mind, understanding other people’s minds, decentration, and mastery of the ability to think purposefully regarding a particular problem. Metacognitive capacities “allow persons to form a detailed picture of their own mental states, of the wishes and intentions of the others, and of the inner and social cues that trigger psychological pain”, according to Lysaker, Erickson et al. (2011, p. 413), “and thereby to cope with challenges and solve complex social problems”. The concept is thus strongly related to the ability to cope with the challenges of everyday life, meaning that impaired metacognitive abilities can have far-reaching consequences (Lysaker, Bob et al., 2013).

Metacognitive problems in schizophrenia appear to be heterogeneous (Lee, Farrow, Spence, & Woodruff, 2004) and stable over time (Hamm et al., 2012; Lysaker, Olesek et al., 2011; Vohs et al., 2014). Even though metacognitive deficits are also found in other psychiatric disorders, metacognition seems to be poorer in people with schizophrenia. Tas, Brown, Aydemir, Brüne, and Lysaker (2014) have found, for example, that understanding one’s own mind is more impaired in people with schizophrenia than in people with bipolar disorder. Taken together, metacognition can be seen as a symptomatic hallmark of schizophrenia (Vohs et al., 2014). In addition, metacognitive deficits seem to be involved in some of the core symptoms of schizophrenia (Morrison, 2001). Bruno, Sachs, Demily, Franck, and Pacherie (2012) and Carruthers (2012) connect deficits in metacognitive monitoring and/or metacognitive control with judgments being easily accepted, and not being corrected in the face of counterevidence. A disturbed sense of agency over thoughts can also be explained by lowered metacognitive control. The most consistent finding, however, is that low metacognition is related to more negative symptoms (MacBeth et al., 2013; Nicolò et al., 2012).

Aims of the Study To address the highlighted issues, the current study explores the relationship between cognitive functioning, metacognition, and social functioning. This study is among the first to examine whether metacognition (as defined by Lysaker et al., 2007) mediates the relationship between cognitive functioning and social functioning. All four domains of metacognition are taken into account. Metacognition, cognitive functioning, and social functioning seem to be closely related. Furthermore, mastery has already been shown to mediate the cognitive functioning-social functioning relationship. Therefore, it is hypothesized that metacognition has a mediating role on the effect of cognitive functioning on social functioning. Finally, given the close involvement of metacognition in symptomatology found in previous literature, significant correlations between metacognition subscales (understanding of oneself, understanding of others, decentration, and mastery) and symptom severity are expected.

Method Participants Participants were recruited from the Metacognitive Reflection and Insight Therapy (MERIT) study, a randomized controlled trial in which a new metacognitive therapy for patients with schizophrenia is being compared to regular treatment (Van Donkersgoed et al., 2014). The MERIT study has been approved by the medical ethical board of the University Medical Center Groningen. The participants were 52 adults diagnosed with schizophrenia or schizoaffective disorder, according to DSM-IV-TR criteria. All of the participants had impaired metacognitive abilities (as measured with the Metacognition Assessment Scale-A; MAS-A; Semerari et al., 2003), and were in a post-acute illness phase (defined by a mean score lower than 4 on positive symptoms on the Positive and Negative Symptom Scale [PANSS] and no change in medication over the past 30 days). Other exclusion criteria were active substance dependence, co-morbid neurological disorders, and impaired intellectual functioning (i.e., IQ below 70). None of the participants has already benefited from some form of metacognitive therapy. There were 36 men and 16 women participating in the study, with a mean age of 38 years (see Table 1 for demographics). Demographic variable N M SD Min Max Gender Men 36 Women 16 Diagnosis Schizophrenia 45 Schizoaffective Disorder 7 First episode psychosis 25 Years since onset of the disorder 13.06 11.38 0 45 Age in years 38.04 11.28 22 59 Materials Confirmation of diagnosis. The Mini International Neuropsychiatric Interview-Plus (M.I.N.I.-Plus; Sheehan et al., 1998) is a structured interview, which is developed to diagnose Axis 1 DSM IV-TR psychiatric disorders, and is used in this study for the confirmation of a diagnosis of schizophrenia or schizoaffective disorder, and the exclusion of substance dependency. The interview takes approximately 20–30 minutes, and is divided into 23 diagnostic categories, spread out over different modules. It features questions on symptoms, rule-outs, disorder subtyping, and chronology. The Dutch version of the M.I.N.I.-Plus 5.0.0. was used (translated by Van Vliet, Leroy, & Van Megen, 2000). Assessment of symptomatology. The Positive and Negative Symptom Scale (PANSS; (Kay, Fiszbein, & Opler, 1987) is a 30-item rating scale, completed by clinically trained researchers on the basis of a semi-structured interview. It assesses the presence and the clinical severity of positive, negative and general symptoms that are associated with schizophrenia. The items range from 1 = absent to 7 = extreme, and the interview takes approximately 45 minutes. In order to exclude florid psychotic patients, a mean score of 7 or higher was used as a cut-off in this study. Assessment of social functioning. The Personal and Social Performance Scale (PSP; Morosini, Magliano, Brambilla, Ugolini, & Pioli, 2000) has been developed specifically for the assessment of social functioning in schizophrenia and is based on the social and occupational dysfunction criterion of the DSM-IV-TR. The PSP assesses psychosocial functioning in four domains: socially useful activities, personal and social relationships, self-care, and disturbing and aggressive behavior. All four domains consist of several criteria, of which the degree of dysfunction is determined on a 6-point scale ranging from 0 = absent to 6 = very severe by the assessor. Assessment of cognitive functioning. The Trail Making Test (TMT), part of the Halstead-Reitan Battery (Reitan & Wolfson, 1985), is primarily used to assess divided attention, cognitive flexibility and processing speed. The TMT A and B scores represent the time in seconds needed to succeed in both tasks. Assessment of cognitive functioning. The Digit Symbol Substitution Test (DSST) is part of the Wechsler Adult Intelligence Scale (Wechsler, 2008), and is used to assess visuomotor processing speed. The total score on this test is based on the amount of correctly completed symbols within 120 seconds. Assessment of metacognition. The Indiana Psychiatric Illness Interview (IPII; Lysaker, Clements, Plascak-Hallberg, Knipscheer, & Wright, 2002) is a semi-structured interview, used to get a spontaneous speech sample of the patients in which metacognitive abilities are reflected. Assessment of metacognition. The adapted Metacognition Assessment Scale (MAS-A; Lysaker et al., 2007) is scored on the basis of the transcript of the IPII. Scoring is performed by a consensus group of at least three trained raters. The four domains of metacognition are reflected in the four ordinal complexity scales of the MAS-A: self-reflectivity, understanding the other’s mind, decentration, and mastery. The raters assign one point for each function on each scale that they judge is accomplished in the transcript. Within each scale, metacognitive capacities are arranged in hierarchical order, so that if evidence for a certain capacity is found, the rater then searches for evidence for the next capacity. If there is no evidence for the presence of that capacity, no evidence is sought for higher capacities. Lysaker et al. (2005) assessed interrater reliability by assessing 12 transcripts with two blind raters. Good overall reliability has been found with an intraclass correlation for the total score of 0.89 and individual scales ranging from 0.83 (understanding of others) to 0.89 (understanding of oneself). To determine which patients meet the inclusion criterion of metacognitive deficits, the following cut-off scores are used in this study: 5.5 out of 9 for self-reflectivity, 4.5 out of 8 for understanding of the other’s mind, 2 out of 3 for decentration, and 4.5 out of 9 for mastery). Participants scoring below cut-off on at least three of these scales fulfill the inclusion criterion of metacognitive deficits (Van Donkersgoed et al., 2014). Procedure The current study makes use of data assembled in the intake and baseline condition of the MERIT study. The intake session took approximately 1.5 hours and was meant to screen the participants for suitability. During the intake session several interviews were conducted, consisting of the M.I.N.I.-Plus 5.0.0., the PANSS and the IPII. After the intake, a transcript of the IPII was assessed by a consensus group, using the MAS-A. If the patients met all of the requirements, a new appointment was made for the baseline assessment, in which the PSP, TMT, and DSST were administered. This baseline assessment session took approximately 2.5 hours. If participants fulfilled both the intake and the baseline assessment, they received €20. If they only fulfilled the intake and not the assessment due to exclusion, they received €10. Data Analyses The analyses were performed using IBM SPSS Statistics 20. First, descriptive and Pearson’s correlational analyses were carried out. The neurocognitive test scores were standardized into percentile scores, after which a Principal Components Analysis was conducted in order to create a single factor score from the three neurocognitive scores. This was used as an independent variable in the mediation model. When all the assumptions for a linear regression were met, the mediation effect was analyzed with a simple mediation model, in which a direct and total effect of cognitive functioning on social functioning (including metacognition as mediator) was assessed (Preacher & Hayes, 2008). Hayes’s (2014) PROCESS macro for SPSS was used for this analysis. Finally, a Sobel test was conducted in order to test whether metacognition influenced the link between cognitive functioning and social functioning (Preacher & Hayes, 2004).

Results Analyses focused on participants’ raw scores on the PSP and MAS-A overall- and subscales, and on standardized percentile scores on the TMT-A and B and DSST. Data inspection shows that the linear regression assumptions were not violated. Means and standard deviations were calculated for each of these variables (see Table 2 for the descriptive statistics). M SD Min Max Social Functioning PSP 57.2 15.3 25 80 Cognitive Functioning TMT-A 17.7 21.4 0 66 TMT-B 20.2 24.9 0 88 DSST 12.2 15.1 0 63 Metacognition MAS Overall 10.7 2.7 3.5 16.0 MAS Understanding Self 4.1 1.0 1.5 6.5 MAS Understanding Others 2.6 0.9 0.5 5.0 MAS Decentration 1.1 0.6 0.0 3.0 MAS Mastery 2.9 1.3 0.0 5.0 A bivariate correlational matrix of social functioning, cognitive functioning, and metacognition shows that there is no significant correlation between these three variables (see Table 3). The TMT subtests significantly correlate with each other (r = 0.41, p = 0.003) and with the Digit Symbol Substitution Test (respectively r = 0.38, p = .006 and r = 0.37, p = .006), meaning that a better performance on the TMT is associated with a better performance on the DSST. Most of the MAS-A scales also correlate with each other. The only exceptions are that mastery does not correlate significantly with understanding of others (r = 0.26, p = .063) and with decentration (r = 0.20, p = .156). Social Cognition Metacognition Scales PSP TMTA TMTB DSST Overall S U D M Social PSP Cogn. TMT-A −0.03 TMT-B 0.13 0.41** DSST 0.06 0.38** 0.37** Metacog. Overall 0.14 −0.07 0.00 0.16 Scale S −0.01 −0.07 −0.02 0.10 0.79** Scale U 0.24 −0.17 −0.04 0.05 0.71** 0.44** Scale D 0.27 −0.18 −0.02 0.12 0.56** 0.28* 0.48* Scale M 0.02 0.11 0.06 0.17 0.76** 0.46** 0.26 0.20 Correlations of symptom severity with metacognition overall- and subscales were computed as well and are presented in Table 4. Negative symptom severity is negatively correlated to metacognition (r = −0.33, p = .017), and in particular to understanding of others (r = −0.38, p = .006). Positive and general symptom severity are not significantly correlated to metacognition, nor to any of the separate subscales. Metacognition Overall S U D M Positive symptom severity −0.08 −0.01 −0.21 −0.07 0.02 Negative symptom severity −0.33* −0.11 −0.38** −0.27 −0.24 General symptom severity 0.11 0.25 0.01 −0.13 0.08 Total symptom severity −0.08 0.09 −0.20 −0.19 −0.03 Next, a principal components analysis of the three cognitive functioning scores was conducted. This produced one factor with an eigenvalue greater than one (eigenvalue = 1.77), which accounted for 59.10 percent of the variance. The factor loadings of each score are shown in Table 5. Factor loadings Trail Making Test A 0.78 Trail Making Test B 0.77 Digit Symbol Substitution Test 0.76 The linear regression of social functioning on cognitive functioning, as conducted with the PROCESS macro in SPSS, shows that there is no significant direct effect of the level of cognitive functioning on the level of social functioning (b = 0.09, p = .446). The regression analysis of the mediator variable metacognition on the independent variable cognitive functioning shows that cognitive functioning does not have a significant effect in predicting a patient’s level of metacognitive functioning (b = 0.04, p = .201). Subsequently, the dependent variable was regressed on both the independent variable and the mediator, as presented in Figure 1. The regression analysis of social functioning on metacognition shows that the level of metacognitive functioning has no significant effect on the prediction of social functioning (b = 0.12, t = 0.12, p = .908). With metacognition added to the model, the direct effect of cognitive functioning on social functioning (b = 0.09, p = .446) is not significantly different from the total effect of cognitive functioning on social functioning (b = 0.78, p = .676; Sobel’s z = 0.09, p = .093, k2 = 0.00). Finally, the analysis was repeated with the four different metacognition scales added as parallel multiple mediators. As is clear from Figure 2, none of the metacognition scales has a significant influence on the relationship between cognitive functioning and social functioning.