Brief assessment of schizotypal traits: A multinational study

Factor structure and measurement invariance of Schizotypal Personality Questionnaire-Brief Revised (Updated) in India

AIM

Schizotypal Personality Questionnaire-Brief Revised-Updated (SPQ-BRU) is an easy-to-conduct, theoretically consistent, and psychometrically better measure of schizotypal personality. However, its study is limited to developed countries. Thus, in the present study, we tested the factor structure and measurement invariance of SPQ-BRU in India.

METHODS

A sample of 734 college students was selected from two sites (n = 614 from Muzaffarnagar in western Uttar Pradesh and n = 120 from Guhana in Haryana). Confirmatory factor analysis was used to test the good fitness of the different models of SPQ-BRU and the measurement invariance across sex and region.

RESULTS

The first-order nine-factor model was a better-fit model (among a set of first-order and second-order models), whereas the second-order three-factor model was a more parsimonious good-fit model of SPQ-BRU. The nine-factor model was strongly invariant across sex and region. Women had higher social anxiety, ideas of reference, and lower constricted affect than men. Moreover, the Gohana sample was higher on several schizotypal personality facades than the Muzaffarnagar sample.

CONCLUSIONS

The present study supported the cross-cultural validity of schizotypal personality and partially established a reliable and valid SPQ-BRU-Hindi language version.

Measurement invariance of brief forms of the Schizotypal Personality Questionnaire across convenience versus random samples

Schizotypy, a multifaceted personality construct that represents liability for schizophrenia, is generally measured with self-report questionnaires that have been developed and validated in samples of undergraduate students. Given that understanding schizotypy in non-clinical samples is essential for furthering our understanding of schizophrenia-spectrum psychopathologies, it is critical to test whether non-clinically identified undergraduate and other convenience samples respond to schizotypy scales in the same way as random samples of the general population. Here, 651 undergraduates, 350 MTurk workers, and two randomly selected high school samples (n = 177, n = 551) completed brief versions of the Schizotypal Personality Questionnaire (SPQ-BR or SPQ-BRU). Multigroup confirmatory factor analysis was used to test whether measurement invariance was present across samples. Tests were made for all samples together and for each pair of samples. Results showed that a first-order nine-factor model fit the data well, and this factor structure displayed configural and metric invariance across the four samples. This suggests that schizotypy has the same factor structure, and the SPQ-BR/BRU is measuring the same construct across the different groups. However, when all groups were compared, results indicated a lack of scalar invariance across these samples, suggesting mean comparisons may be inappropriate across different sample types. However, when randomly selected high school students were compared with undergraduate students, scalar invariance was present. This suggests that factors such as culture and form type may be driving invariance, rather than sampling method (convenience vs general population).

Comparing two measures of schizotypy and their relationship with psychological distress in British university students

AIMS

Schizotypy reflects the vulnerability to schizophrenia in the general population. Different questionnaires have been developed to measure aspects of schizotypy. Higher schizotypy scores have also been linked with depression, anxiety, and stress sensitivity. Here we examine the associations of schizotypy with symptoms of depression and anxiety in a sample of university students, using two different measures (N = 271).

METHODS

A series of confirmatory factor analyses was used to examine two distinct and frequently employed measures of schizotypy: the Community Assessment of Psychic Experiences (CAPE), and the Schizotypy Personality Questionnaire (SPQ). We assessed their relationship with each other and their predictive validity for anxiety, depression, and stress sensitivity.

RESULTS

Our results indicated the brief 7-factor SPQ (SPQ-BR) factor solution for the SPQ and the 15-item and 3 factor solution for the CAPE (i.e., CAPE-P15) as best fitting models. Particularly the CAPE dimension of persecutory ideation was a strong predictor of anxiety, depression, and stress sensitivity, whereas the SPQ dimensions of no close friends and social anxiety predicted psychological distress and stress in our student sample.

CONCLUSIONS

Our findings extend earlier work in general and patient samples and point to the importance of understanding the contribution of particularly positive schizotypy symptoms and different interpersonal aspects to psychological distress.

Increased structural connectivity in high schizotypy

The link between brain structural connectivity and schizotypy was explored in two healthy participant cohorts, collected at two different neuroimaging centres, comprising 140 and 115 participants, respectively. The participants completed the Schizotypal Personality Questionnaire (SPQ), through which their schizotypy scores were calculated. Diffusion-MRI data were used to perform tractography and to generate the structural brain networks of the participants. The edges of the networks were weighted with the inverse radial diffusivity. Graph theoretical metrics of the default mode, sensorimotor, visual, and auditory subnetworks were derived and their correlation coefficients with the schizotypy scores were calculated. To the best of our knowledge, this is the first time that graph theoretical measures of structural brain networks are investigated in relation to schizotypy. A positive correlation was found between the schizotypy score and the mean node degree and mean clustering coefficient of the sensorimotor and the default mode subnetworks. The nodes driving these correlations were the right postcentral gyrus, the left paracentral lobule, the right superior frontal gyrus, the left parahippocampal gyrus, and the bilateral precuneus, that is, nodes that exhibit compromised functional connectivity in schizophrenia. Implications for schizophrenia and schizotypy are discussed.

Activity system, schizotypal personality, and mentalization: A study between halted activity and COVID-19 conducted in Henan, China

The pandemic-related lifestyle has potentially imposed crucial disturbances on daily and long-term activities, which, in turn, were associated with thought disturbance. This study investigates how the characteristics of the activity system during pandemic-related restrictions are associated with other psychomental aspects. By focusing on PTSD, mentalization, and schizotypal personality, and by inquiring about the main components of the activity system of 852 college students (Zhengzhou, Henan, China)- including the goals orienting their activity, goals' terms and types, the motivation levels and sources, the activity type and engagement time, the flow of the activity, and how due to pandemic lifestyle-results revealed that the activity system's components have significant associations with PTSD, reflective function, and schizotypal traits. Additionally, some of the activity system's elements have a significant predictive role regarding schizotypal traits. The study considered that the life narrative during the pandemic has been disturbed; hence, this may have a crucial effect on mind coherence. Additionally, the outcomes from the pandemic context will support mental health interventions in other similar contexts where the life narrative is severely affected.

Thinking style and psychosis proneness do not predict false insights

The FIAT paradigm (Grimmer et al., 2021) is a novel method of eliciting 'Aha' moments for incorrect solutions to anagrams in the laboratory, i.e. false insights. There exist many documented reports of psychotic symptoms accompanying strong feelings of 'Aha!' (Feyaerts, Henriksen, Vanheule, Myin-Germeys, & Sass, 2021; Mishara, 2010; Tulver, Kaup, Laukkonen, & Aru, 2021), suggesting that the newly developed FIAT could reveal whether people who have more false insights are more prone to psychosis and delusional belief. To test this possibility, we recruited 200 participants to take an adapted version of the FIAT and complete measures of thinking style and psychosis proneness. We found no association between experimentally induced false insights and measures of Schizotypy, Need for Cognition, Jumping to Conclusions, Aberrant Salience, Faith in Intuition, or the Cognitive Reflection Task. We conclude that experiencing false insights might not be constrained to any particular type of person, but rather, may arise for anyone under the right circumstances.

The effect of schizotypy on spatial learning in an environment with a distinctive shape

In two experiments, participants completed the Oxford-Liverpool Inventory of Feelings and Experiences measuring schizotypal traits across four dimensions (unusual experiences, cognitive disorganization, introvertive anhedonia, and impulsive non-conformity). They then took part in a virtual navigation task where they were required to learn about the position of a hidden goal with reference to geometric cues of a rectangular arena or rely on colored wall panels to find the hidden goal in a square-shaped arena. Unusual experience and cognitive disorganization were significant predictors of the use of geometric cues, but no significant predictors were found for the use of wall panels. Implications to hippocampal function and the clinical domain are considered.

Comparing psychotic experiences in low-and-middle-income-countries and high-income-countries with a focus on measurement invariance

BACKGROUND

The prevalence of psychotic experiences (PEs) is higher in low-and-middle-income-countries (LAMIC) than in high-income countries (HIC). Here, we examine whether this effect is explicable by measurement bias.

METHODS

A community sample from 13 countries (N = 7141) was used to examine the measurement invariance (MI) of a frequently used self-report measure of PEs, the Community Assessment of Psychic Experiences (CAPE), in LAMIC (n = 2472) and HIC (n = 4669). The CAPE measures positive (e.g. hallucinations), negative (e.g. avolition) and depressive symptoms. MI analyses were conducted with multiple-group confirmatory factor analyses.

RESULTS

MI analyses showed similarities in the structure and understanding of the CAPE factors between LAMIC and HIC. Partial scalar invariance was found, allowing for latent score comparisons. Residual invariance was not found, indicating that sum score comparisons are biased. A comparison of latent scores before and after MI adjustment showed both overestimation (e.g. avolition, d = 0.03 into d = -0.42) and underestimation (e.g. magical thinking, d = -0.03 into d = 0.33) of PE in LAMIC relative to HIC. After adjusting the CAPE for MI, participants from LAMIC reported significantly higher levels on most CAPE factors but a significantly lower level of avolition.

CONCLUSION

Previous studies using sum scores to compare differences across countries are likely to be biased. The direction of the bias involves both over- and underestimation of PEs in LAMIC compared to HIC. Nevertheless, the study confirms the basic finding that PEs are more frequent in LAMIC than in HIC.

Polygenic risk for schizophrenia and schizotypal traits in non-clinical subjects

BACKGROUND

Schizotypy is a putative risk phenotype for psychosis liability, but the overlap of its genetic architecture with schizophrenia is poorly understood.

METHODS

We tested the hypothesis that dimensions of schizotypy (assessed with the SPQ-B) are associated with a polygenic risk score (PRS) for schizophrenia in a sample of 623 psychiatrically healthy, non-clinical subjects from the FOR2107 multi-centre study and a second sample of 1133 blood donors.

RESULTS

We did not find correlations of schizophrenia PRS with either overall SPQ or specific dimension scores, nor with adjusted schizotypy scores derived from the SPQ (addressing inter-scale variance). Also, PRS for affective disorders (bipolar disorder and major depression) were not significantly associated with schizotypy.

CONCLUSIONS

This important negative finding demonstrates that despite the hypothesised continuum of schizotypy and schizophrenia, schizotypy might share less genetic risk with schizophrenia than previously assumed (and possibly less compared to psychotic-like experiences).

Examining subjective experience of aberrant salience in young individuals at ultra-high risk (UHR) of psychosis: A 1-year longitudinal study

Aberrant salience (AS) is considered as a predisposing factor in early psychosis. Although it has been frequently examined in the general population as a measure of vulnerability to psychotic disorder, empirical evidence on AS in prodromal phases of psychosis is still relatively scarce. Thus, the aims of this research were (1) to investigate any significant association of AS with functioning, psychopathology and treatment components of an "early intervention in psychosis" program in a sample of young community help-seekers at Ultra-High Risk (UHR) of psychosis along a 1-year follow-up period, and (2) to longitudinally monitor the stability of AS across the 1 year of follow-up. Participants (87 UHR), aged 13-35 years, completed the Aberrant Salience Inventory (ASI), the Comprehensive Assessment of At-Risk Mental States (CAARMS) and the brief version of the Schizotypal Personality Questionnaire (SPQ-B) at baseline and after the 1 year of follow-up. Spearman correlation analyses among psychopathological parameters and specialized treatment components were performed. A multiple linear regression analysis was also carried out. After a 1-year follow-up period, UHR subjects had a statistically relevant decrease in ASI total scores. This was significantly related to the number of individual cognitive-behavioral therapy (CBT) sessions and the number of family psychoeducational sessions offered to UHR participants and their family members during the same 12-month period. In conclusion, AS is clinically relevant in UHR individuals. However, it seems to improve over time along with the delivery of tailored, specialized psychosocial interventions for early psychosis.

Subjective experience of aberrant salience in young people at Ultra-High Risk (UHR) for psychosis: a cross-sectional study

PURPOSE

Aberrant salience (AS) is conceptualized as a potential predisposing factor for psychotic states of mind. Despite several studies in the general population, research on AS in the early phases of psychosis is still relatively scarce. The aim of this cross-sectional study is (1) to evaluate the AS subjective experience in Ultra-High Risk (UHR) adolescents and young adults compared to help-seeking peers with First Episode Psychosis (FEP) and (2) to assess any significant association of baseline AS with psychopathology and functioning in UHR participants.

MATERIALS AND METHODS

Participants (87 UHR and 139 FEP), aged 13-35 years, completed the Comprehensive Assessment of At-Risk Mental States (CAARMS), the Aberrant Salience Inventory (ASI) and the brief version of the Schizotypal Personality Questionnaire (SPQ-B). Within the UHR subgroup, Spearman correlation and multiple linear regression analyses among psychopathological parameters were performed.

RESULTS

No difference in baseline AS subjective levels was found between UHR and FEP participants (median [interquartile range]: 14.50 [7-19] vs 14 [9-21]; z = -1.576; p = 0.115). In UHR individuals, the ASI total score was significantly associated with attenuated positive symptoms (ρ = 0.284, p = 0.008), depression (ρ = 0.256; p = 0.018) and specific schizotypal personality traits (i.e. cognitive-perceptual deficits and disorganization [respectively, ρ = 0.487, p = 0.001, and ρ = 0.295, p = 0.008]).

CONCLUSIONS

AS is clinically relevant in UHR subjects, comparable to FEP patients. Moreover, it seems to mutually interact with schizotypy in the clinical manifestation of attenuated positive psychopathology.

Psychosocial Stress, Social Support, and the Escalation of Schizotypal Symptoms

ABSTRACT

Although research suggests that psychosocial stress is associated with an increase in schizotypal symptoms, the type of stressor associated with increased symptomatology is unclear, and no study has examined whether social support might mitigate the effects of stress on symptom change. In this study, 131 young adults completed measures of schizotypal symptoms, major life events, daily hassles, and perceptions of social support at baseline, and measures of stress and symptoms again 4 to 6 weeks later. Results indicated, after controlling for baseline measures, that for those scoring low on schizotypal measures at baseline, only low levels of social support were associated with increased symptoms. For those scoring high on the schizotypal scales at baseline, however, both major life events and daily hassles were associated with increased symptomatology, but only when perceptions of social support at baseline were low. The results suggest that it is important to assess both perceptions of social support and baseline symptomatology when examining whether major life events and daily stress are associated with increased psychotic symptoms. Both types of psychosocial stress are associated with an increase in symptoms, but only for those who are already showing above average symptoms and only when social support is low.

The Latent Structure of Negative Symptoms in the General Population in Adolescence and Emerging Adulthood

Negative symptoms predict adverse outcomes within psychotic disorders, in individuals at high-risk for psychosis, and in young people in the community. There is considerable interest in the dimensional structure of negative symptoms in clinical samples, and accumulating evidence suggests a 5-factor structure. Little is known about the underlying structure of negative symptoms in young people despite the importance of this developmental stage for mental health. We used confirmatory factor analysis to test the structure of parent-reported negative symptoms at mean ages 16.32 (SD 0.68, N = 4974), 17.06 (SD 0.88, N = 1469) and 22.30 (SD 0.93, N = 5179) in a community sample. Given previously reported associations between total negative symptoms and genome-wide polygenic scores (GPS) for major depressive disorder (MDD) and schizophrenia in adolescence, we assessed associations between individual subdomains and these GPSs. A 5-factor model of flat affect, alogia, avolition, anhedonia, and asociality provided the best fit at each age and was invariant over time. The results of our linear regression analyses showed associations between MDD GPS with avolition, flat affect, anhedonia, and asociality, and between schizophrenia GPS with avolition and flat affect. We showed that a 5-factor structure of negative symptoms is present from ages 16 to 22 in the community. Avolition was most consistently associated with polygenic liability to MDD and schizophrenia, and alogia was least associated. These findings highlight the value of dissecting negative symptoms into psychometrically derived subdomains and may offer insights into early manifestation of genetic risk for MDD and schizophrenia.

Striatal GABA level is associated with sensory integration ability in individuals with low levels of negative schizotypy

Recent studies suggest that altered gamma-aminobutyric acidergic (GABAergic) function may result in multisensory integration deficits in schizophrenia. However, it is unclear whether the GABA level is abnormal in individuals with high levels of schizotypal traits and how it would correlate with sensory integration ability in these individuals. This study aimed to compare the GABA level between individuals with high and low levels of negative schizotypy, and examine the relationship between GABA levels and sensory integration ability in each group. In vivo GABA+ and N-acetylaspartate (NAA) levels in the striatum were measured using proton magnetic resonance imaging in 19 participants with high levels of negative schizotypy and 21 participants with low levels of negative schizotypy. The Sensory Integration subscale of the abridged version of the Cambridge Neurological Inventory was used. We examined the group differences in GABA+/NAA levels, and the correlation between striatal GABA+/NAA levels and sensory integration ability in each group. The two groups showed comparable levels of in-vivo GABA+/NAA. In-vivo GABA+/NAA levels were negatively correlated with sensory integration score in participants with low levels of negative schizotypy, but not in participants with high levels of negative schizotypy. Our findings indicate that the increased GABA level is correlated with better sensory integration ability in individuals with low levels of negative schizotypy, implicating the role of GABAergic function in multisensory integration. Unlike schizophrenia patients, individuals with high levels of schizotypy do not exhibit any abnormality in their GABAergic system and sensory integration ability.

Bifactor Structure of the Schizotypal Personality Questionnaire Across the Schizotypy Spectrum

Despite widespread use in schizophrenia-spectrum research, uncertainty remains around an empirically supported and theoretically meaningful factor structure of the Schizotypal Personality Questionnaire (SPQ). Current identified structures are limited by reliance on exclusively nonclinical samples. The current study compared factor structures of the SPQ in a sample of 335 nonpsychiatric individuals, 292 schizotypy-spectrum individuals (schizophrenia, schizoaffective disorder, or schizotypal personality disorder), and the combined group (N = 627). Unidimensional, correlated, and hierarchical models were assessed in addition to a bifactor model, wherein subscales load simultaneously onto a general factor and a specific factor. The best-fitting model across samples was a two-specific factor bifactor model, consistent with the nine symptom dimensions of schizotypy as primarily a direct manifestation of a unitary construct. Such findings, for the first time demonstrated in a clinical sample, have broad implications for transdiagnostic approaches, including reifying schizotypy as a construct underlying diverse manifestations of phenomenology across a wide range of severity.

Association between traumatic stressful events and schizotypal symptoms among a community-based sample of adolescents: A 2-year longitudinal study

BACKGROUND

Traumatic stressful events (TSEs) are among the most studied risk factors for subsequent schizotypal symptoms. However, specificity and aggregate effects of trauma exposure on schizotypal symptoms remain unclear. This study investigates these relationships among a community-based sample of US adolescents.

MATERIAL AND METHODS

A sub-sample of 426 adolescents (51.6% female) from the Philadelphia Neurodevelopmental Cohort study were selected for longitudinal follow-up based on presence (n = 209) or absence (n = 217) of psychosis spectrum symptoms (PSS). At baseline, they completed assessments of demographic, TSEs, other psychopathology (e.g., PSS, anxiety, depression, and behavioral disorder) and family history of psychopathology. Schizotypal symptom dimensions (cognitive-perceptual, interpersonal and disorganized) were evaluated approximately two years later.

RESULTS

More than half of adolescents experienced at least one type of TSE. Adolescents with assaultive trauma reported about 1.5 times as many symptoms on all three schizotypal symptom dimensions, compared to adolescents with non-assaultive TSE, adjusting for demographic and family history variables. No statistical significance was found after further adjusting for other baseline psychopathology (p > 0.05). There was a significant aggregate effect of TSEs on cognitive-perceptual symptoms with small effect size (p < 0.001, Cohen's f² = 0.034).

CONCLUSIONS

We found evidence of an association between aggregate TSEs and cognitive-perceptual symptoms, but trauma type was not associated with schizotypal symptom dimensions when controlling for potential confounders. Our findings highlight the importance of considering aggregate TSE effects and potential confounds when examining associations between TSEs and schizotypy. Trauma and psychosis spectrum screening may be important in the effort to provide trauma-informed care.

Subclinical schizotypal vs. autistic traits show overlapping and diametrically opposed facets in a non-clinical population

BACKGROUND

The overlap of autism spectrum disorder (ASD) and psychosis or schizophrenia spectrum disorders (SSD) has exposed problems central to conceptualising and understanding co-morbidity in psychiatric disorders.

METHODS

In the present study, we demonstrate that a deep phenotyping approach aids clarification of both overlapping and diametrically opposed features of ASD and SSD on the level of trait facets.

RESULTS

We first show overlap of negative and disorganised (but not positive) features of schizotypy with autistic traits in a sample of n = 376 German non-clinical subjects using multiple psychometric measures of schizotypy (MSS multidimensional schizotypy scale, OLIFE Oxford-Liverpool Inventory of Feelings and Experiences, and SPQ-B schizotypal personality questionnaire - brief) and the AQ autism spectrum quotient, with control measures for affective spectrum pathology (BDI). Findings were then replicated in a French-Swiss sample (n = 264) using MSS, OLIFE, AQ, and in addition the Community Assessment of Psychic Experiences (CAPE). Additional principal component analysis confirmed our finding of the co-existence of both overlapping (loss of function, social communication deficit, and negative schizotypy) as well as diametrically opposed features (AQ attention to detail, positive schizotypy) across the two spectra. Results were validated with Horn's parallel analyses, affirming two component solutions, and PCA using sample-specific, factor-analysis-derived schizotypy scores.

CONCLUSIONS

Providing a framework for multi-dimensional transdiagnostic characterisation of ASD vs. SSD phenotypes we point out overlapping vs. discriminating facets. In addition to the use of novel multidimensional schizotypy scales, it also shows transcultural consistency of findings, and highlights a particular role for the attention to detail AQ subscale.

Borderline and schizotypal traits in college students: Relationship and personality profiles

The relationships between borderline and schizotypal traits are still debated. Borderline traits, schizotypal traits, and several psychopathological symptoms were assessed among 2,341 college students. A factor analysis was performed on borderline and schizotypal personality measures, leading to 10 factors. Borderline factors were largely intercorrelated, as were schizotypal factors. Moreover, borderline factors were weakly to largely correlated to schizotypal factors. Five factors were very strongly correlated (r > .50). Dissociation was strongly related to Odd Beliefs/Unusual Perceptive Experiences and Anxious-Depressive factors. Social Anxiety was strongly related to Suspiciousness. Based on these 10 factors, a cluster analysis was conducted, and resulted in four clearly distinct groups: a Low Traits cluster, a Narcissistic cluster, a Social Anxiety cluster, and a High Traits cluster. This High Traits cluster had the lowest levels of academic achievement and the highest levels of internalizing behaviors and externalizing behaviors. The clinical implications of the results are discussed.

The Schizotypal Personality Questionnaire for Children (SPQ-C): Factor Structure, Child Abuse, and Family History of Schizotypy

There is a relative dearth of research on features of schizotypal personality in children, in part due to lack of instrumentation. This study tests 5 competing models of the factor structure of the self-report Schizotypal Personality Questionnaire for Children (SPQ-C) and examines its relationship with a family history of schizotypal personality disorder (SPD), child abuse, and stability over time. Hypotheses were tested on 454 11- to 12-year-old schoolchildren and their caregivers. Confirmatory factor analyses supported a 3-factor structure of the SPQ-C (cognitive-perceptual, interpersonal, and disorganized). Test-retest stability was relatively robust over 3 months (r = .67), 6 months (r = .64), and 12 months (r = .55), with acceptable internal reliabilities (r = .84 to .91). Regarding construct validity, children with a biological family history of SPD had higher scores on all 3 factors (d =.51). Abused children had higher schizotypy scores (d = .55). A genetic × environment interaction was observed, with schizotypy highest in those with both a family history of schizotypy and also child abuse. Findings are the first in the child schizotypy field to document a gene × environment interaction and the independence of child abuse from confounding genetic influences. Results support the utility of the SPQ-C in future family and clinical studies of schizotypal personality and provide an avenue for much-needed and neglected research into the early antecedents of child schizotypal personality.

The association of striatal volume and positive schizotypy in healthy subjects: intelligence as a moderating factor

BACKGROUND

Schizotypy, a putative schizophrenia endophenotype, has been associated with brain-structural variations partly overlapping with those in psychotic disorders. Variations in precuneus structure have been repeatedly reported, whereas the involvement of fronto-striatal networks - as in schizophrenia - is less clear. While shared genetic architecture is thought to increase vulnerability to environmental insults, beneficial factors like general intelligence might buffer their effect.

METHODS

To further investigate the role of fronto-striatal networks in schizotypy, we examined the relationship of voxel- and surface-based brain morphometry and a measure of schizotypal traits (Schizotypal Personality Questionnaire, with subscores Cognitive-Perceptual, Interpersonal, Disorganised) in 115 healthy participants [54 female, mean age (s.d.) = 27.57(8.02)]. We tested intelligence (MWT-B) as a potential moderator.

RESULTS

We found a positive association of SPQ Cognitive-Perceptual with putamen volume (p = 0.040, FWE peak level-corrected), moderated by intelligence: with increasing IQ, the correlation of SPQ Cognitive-Perceptual and striatal volume decreased (p = 0.022). SPQ Disorganised was positively correlated with precentral volume (p = 0.013, FWE peak level-corrected). In an exploratory analysis (p < 0.001, uncorrected), SPQ total score was positively associated with gyrification in the precuneus and postcentral gyrus, and SPQ Disorganised was negatively associated with gyrification in the inferior frontal gyrus.

CONCLUSIONS

Our findings support the role of fronto-striatal networks for schizotypal features in healthy individuals, and suggest that these are influenced by buffering factors like intelligence. We conclude that protective factors, like general cognitive capacity, might attenuate the psychosis risk associated with schizotypy. These results endorse the idea of a continuous nature of schizotypy, mirroring similar findings in schizophrenia.

Anhedonia in young people with first episode psychosis: a longitudinal study

Aim: Previous research observed deficits in pleasure experience in chronic schizophrenia, but little is known about anhedonia in early psychosis. Aim of this study is: (1) to examine anhedonia in distinct help-seeking subgroups of young people identified through the First Episode Psychosis (FEP) criteria, (2) to investigate its correlations with psychopathology in the FEP sample, and (3) to monitor longitudinally its stability in the FEP group along 1-year follow-up period.Materials and methods: All participants (137 FEP and 95 nonpsychotic psychiatric controls [i.e. non-FEP]), aged 13-35 years, completed the Comprehensive Assessment of At-Risk Mental States (CAARMS), the Schizotypal Personality Questionnaire - Brief version (SPQ-B), the Brief O-LIFE questionnaire (BOL), and the World Health Organization Quality of Life - Brief version (WHOQOL-BREF). We used two different indexes of anhedonia: CAARMS 'Anhedonia' item 4.3 and BOL 'Introvertive Anhedonia' subscale scores.Results: In comparison with non-FEP, FEP patients showed higher baseline anhedonia scores. After 1-year follow-up period, FEP individuals had a significant decrease in severity of anhedonia scores. In the FEP group, anhedonia showed significant, enduring (over time) correlations with impaired role functioning, negative symptoms, comorbid depression, poorer self-perceived quality of life and specific schizotypal personality traits (i.e. interpersonal deficits).Conclusions: Anhedonia is relevant in the early phase of psychosis and its severity is associated with functioning deterioration and a bad quality of life.

Exploring the Relationship Between Schizotypal Traits and Dispositional Mindfulness From a Network Perspective

Schizotypy has been associated with impairment in social cognition (e.g., emotional processing, social perception, Theory of Mind). To our knowledge, no study has investigated these processes in terms of dispositional mindfulness. This study aimed to use network theory to explore the relationship between dispositional mindfulness dimensions and schizotypal traits. Participants were 1572 college students who completed the Five Facet Mindfulness Questionnaire-Short Form (FFMQ-SF) and the Schizotypal Personality Questionnaire-Brief (SPQ-B). We first estimated a Gaussian Graphical Model including the FFMQ-SF and the SPQ-B dimensions. We then computed centrality indices and predictability, and we finally conducted a bootstrapping procedure to assess the accuracy of edge weights and the stability of the centrality indices. Describing was strongly and negatively related to interpersonal schizotypy. Acting with awareness and nonjudgment shared negative edges with interpersonal schizotypy. These results provide potential keys to understand alexithymia, decreased sense of self-agency, and emotion regulation in schizotypy.

Validation of the Chinese version of the Multidimensional Schizotypy Scale (MSS): Convergent evidence from exploratory and confirmatory factor analyses

BACKGROUND

Schizotypy has been shown to be a time-stable construct that exists across the schizophrenia spectrum. The Multidimensional Schizotypy Scale (MSS) was developed to capture the three factors underlying schizotypy: positive, disorganized and negative schizotypy. However, a recent validation study reported a four-factor construct with an additional negative social anhedonia factor. The factor structure of the Chinese version of the MSS remains unknown. This study aimed to identify and validate the factor structure of the Chinese version of the MSS.

METHODS

We recruited 641 Chinese speakers via on-line advertisement. We administered the Chinese version of the MSS, which was a self-report instrument. The scale consists of 77 items with true or false response options. We identified and removed 43 outliers. Finally, a total of 294 participants were randomly selected as the derivative sample for exploratory factor analysis (EFA). The remaining 304 participants were retained as the validation sample for confirmatory factor analysis (CFA).

RESULTS

EFA identified four factors: the positive factor, the disorganization factor, the negative affective and motivational anhedonia factor, and the negative social anhedonia factor. The EFA-identified four-factor model was compared with the unidimensional, three-factor bifactorial and theoretical three-factor models using CFAs. The three-factor bifactorial model fitted the data better than the EFA-identified four-factor model.

CONCLUSION

Our finding suggests that the Chinese version of the MSS is a valid tool for assessing schizotypy in the Chinese setting.

Schizotypal traits in Swedish speaking psychiatric patients and non-psychiatric controls

Introduction: Recently, schizotypal personality traits were measured in a multinational sample recruited from 14 countries, however no Scandinavian cohort was included. The aim of this study was, therefore, to measure schizotypal personality traits in Swedish-speaking populations, with and without psychiatric disorders, and to investigate the psychometric properties of the Swedish version of the Schizotypal Personality Questionnaire-Brief (SPQ-B).Methods: The SPQ-B results from 50 psychiatric patients were compared to controls (n = 202). An additional sample of 25 controls completed the full SPQ twice and we calculated test-retest reliability for SPQ and SPQ-B. We estimated the internal consistency for SPQ-B and SPQ-B factors with omega. We compared the results of SPQ-B (M and SD) in patient and control groups to corresponding results worldwide.Results: We found similarity between our SPQ-B scores and those from other published samples. SPQ-B showed good internal consistency and acceptable test-retest correlations. The results indicate that the Swedish version of the instrument is valid and can differentiate psychiatric cohorts from non-psychiatric controls.Conclusion: The Swedish version of the SPQ-B exhibit good psychometric properties and is useful for assessing schizotypal traits in clinical and non-clinical populations.

Positive Schizotypy Increases the Acceptance of Unpresented Materials in False Memory Tasks in Non-clinical Individuals

Enhanced spreading of semantic activation has been hypothesized to underlie some of the most significant symptoms of schizotypal personality, like thought disorder, odd speech, delusion, or magical thinking. We applied the Deese/Roediger-McDermott false memory task to the study of semantic activation in a group of 123 non-clinical individuals varying in the three dimensions of schizotypal personality: positive, negative and disorganized schizotypy. In the study phase, we presented them with lists composed of words semantically associated to unpresented critical words. Then, they responded to a recognition questionnaire including previously presented words and critical unpresented lures, as well as weakly related and unrelated unpresented lures. Participants rated their confidence in recognizing each word. They also filled in a standardized schizotypal personality questionnaire. Confirming the false memory effect, recognition ratings provided in response to critical words were higher than those produced for both weakly related and unrelated items. Crucially, scores in the positive dimension increased recognition percentages and confidence ratings for weakly related and unrelated lures. This study indicates that high levels of positive schizotypy might influence the tendency to accept false memories of unrelated unpresented material.

Common Taxonomy of Traits and Symptoms: Linking Schizophrenia Symptoms, Schizotypy, and Normal Personality

The associations among normal personality and many mental disorders are well established, but it remains unclear whether and how symptoms of schizophrenia and schizotypal traits align with the personality taxonomy. This study examined the joint factor structure of normal personality, schizotypy, and schizophrenia symptoms in people with psychotic disorders (n = 288) and never-psychotic adults (n = 257) in the Suffolk County Mental Health Project. First, we evaluated the structure of schizotypal (positive schizotypy, negative schizotypy, and mistrust) and normal traits. In both the psychotic-disorder and never-psychotic groups, the best-fitting model had 5 factors: neuroticism, extraversion, conscientiousness, agreeableness, and psychoticism. The schizotypy traits were placed on different dimensions: negative schizotypy went on (low) extraversion, whereas positive schizotypy and mistrust went on psychoticism. Next, we added symptoms to the model. Numerous alternatives were compared, and the 5-factor model remained best-fitting. Reality distortion (hallucinations and delusions) and disorganization symptoms were placed on psychoticism, and negative symptoms were placed on extraversion. Models that separated symptom dimensions from trait dimensions did not fit well, arguing that taxonomies of symptoms and traits are aligned. This is the first study to show that symptoms of psychosis, schizotypy, and normal personality reflect the same underlying dimensions. Specifically, (low) extraversion, negative schizotypy, and negative symptoms form one spectrum, whereas psychoticism, positive schizotypy, and positive and disorganized symptoms form another. This framework helps to understand the heterogeneity of psychosis and comorbidity patterns found in psychotic disorders. It also underscores the importance of traits to understanding these disorders.

Schizotypal Personality Questionnaire-Brief: Effect of invalid responding on factor structure analysis and scores of schizotypy

OBJECTIVES

We assessed the effect of invalid responding on factor structure and on scores of schizotypy through the factor analysis of the Schizotypal Personality Questionnaire-Brief (SPQ-B) in a sample of 580 Romanian students using 3 validity items and 5 social desirability items.

METHODS

We examined the factor structure of the SPQ-B, we compared the mean SPQ-B scores between reliable and unreliable responders and between high vs. low social desirability responders, and we re-run the factor analysis restricting the sample to the reliable or low social desirability responders.

RESULTS

Factor analysis resulted in a 3-factor solution: Cognitive-perceptual, Interpersonal and Disorganized dimensions. Unreliable responders had lower scores of positive, negative and total schizotypy. Subjects with high social desirability scores had lower scores of disorganized schizotypy. Factor analyses in the samples of "good" responders showed minor differences in reliable responders, whereas, after taking into account the effect of social desirability, 2 items correctly loaded on expected dimensions.

CONCLUSIONS

Random responding and social desirability could influence scores of schizotypy and factor structure. Simple methods could be used to identify invalid responses. The effect of social desirability could be linked to the phrasing of items.

Screening nursing students to identify those at high risk of poor mental health: a cross-sectional survey

OBJECTIVES

This study aimed to identify those at high risk of poor mental health among nursing students and to examine the relationships and consistency among five mental health assessments.

DESIGN

A cross-sectional design with purposive sampling was used. Four mental health screening tools plus previous mental health history/information were conducted during June 2015 to October 2016.

SETTING

A nursing major university in Taiwan.

PARTICIPANTS

A total of 2779 participants aged between 19 and 45 years were recruited.

MAIN OUTCOME MEASURES

Five mental health risks were identified: increased risk for ultra-high risk, putative prepsychosis states, high trait anxiety, high state anxiety with genetic risk and depression.

RESULTS

Out of the 3395 collected questionnaire, 2779 (82%) were found valid and included in the study. 612 (22%) of the participants were identified to be at mental health risk. 12 of them appeared positive in four, 79 in three, 148 in two and 373 in one of the adopted mental health screening tools. 69 participants had the experience of seeking medical help due to mental health issues, and 58% of them were identified to be at risk of mental health during the screening. Trait and state anxiety scored the highest in correlation analysis (r(2620)=0.76, p<0.001). Correlations were observed in the scores on the subscales of Chinese Version of Schizotypal Personality Questionnaire-Brief (CSPQ-B) and those of Brief self-report Questionnaire for Screening Putative Prepsychotic States (BQSPS), and the highest correlation coefficients was (r(2740)=0.70, p<0.001). Although both of the screening tools are used to assess mental illness risk at its prodromal phase, but CSPQ-B in general appeared to have more rigorous screening criteria than BQSPS.

CONCLUSION

For expediting early identification high risk of poor mental health, easy-to-use screening questionnaires can be adopted to assess the mental health state of nursing students whose mental well-being and overall health are of vital importance to the entire healthcare industry.

The network structure of schizotypal personality traits in a population-based sample

Outcomes for people with schizophrenia-spectrum disorders (SSDs) are generally poor, making it important to understand risk states and illness transition. The network approach, which conceptualizes psychopathology as a network of causally interacting symptoms, may hold promise in this regard. Here, we present a network analysis of schizotypal personality traits (i.e., schizophrenia-like cognitive, perceptual, affective, interpersonal, and behavioral anomalies that may index one's vulnerability for a SSD) using an international sample. We analyzed data from 9505 participants between the ages of 14-70 who completed the Schizotypal Personality Questionnaire-Brief on TestMyBrain.org. In line with other research, we find that the network of schizotypal traits is densely connected, characterized by three communities of items-interpersonal (I), disorganized (D), cognitive-perceptual (CP)-with I and D features exhibiting the greatest centrality (z-scored M strength: I = 0.56, D = 0.29, CP = -0.84; expected influence: I = 0.54, D = 0.33, CP = -0.84) and predictability (M I = 0.37, D = 0.43, CP = 0.23). Importantly, within our sample, we found the estimated network to be replicable (Network Comparison Test: network structure difference: M = 0.304, p = .420; global strength difference: S = 0.904, p = .530), and estimates of node centrality to be stable (correlation-stability coefficient = 0.75). Further, we find network differences between certain groups differing in levels of SSD risk as a function of age (network structure: difference M = 0.562, p < .001; global strength difference: S = 3.483, p = .012) and ethnic minority status (global strength difference: S = 11.488, p = .004). Together, these findings demonstrate the utility of using network approaches to understand SSD risk states as well as the replicability of network findings on schizotypal personality traits and related SSD risk concepts.

Associations of schizophrenia risk genes ZNF804A and CACNA1C with schizotypy and modulation of attention in healthy subjects

Schizotypy is a multidimensional risk phenotype distributed in the general population, constituting of subclinical, psychotic-like symptoms. It is associated with psychosis proneness, and several risk genes for psychosis are associated with schizotypy in non-clinical populations. Schizotypy might also modulate cognitive abilities as it is associated with attentional deficits in healthy subjects. In this study, we tested the hypothesis that established genetic risk variants ZNF804A rs1344706 and CACNA1C rs1006737 are associated with psychometric schizotypy and that schizotypy mediates their effect on attention or vice versa. In 615 healthy subjects from the FOR2107 cohort study, we analysed the genetic risk variants ZNF804A rs1344706 and CACNA1C rs1006737, psychometric schizotypy (schizotypal personality questionnaire-brief SPQB), and a neuropsychological measure of sustained and selective attention (d2 test). ZNF804A rs1344706 C (non-risk) alleles were significantly associated with higher SPQ-B Cognitive-Perceptual subscores in women and with attention deficits in both sexes. This schizotypy dimension also mediated the effect of ZNF804A on attention in women, but not in men. CACNA1C rs1006737-A showed a significant sex-modulated negative association with Interpersonal schizotypy only in men, and no effect on attention. Our multivariate model demonstrates differential genetic contributions of two psychosis risk genes to dimensions of schizotypy and, partly, to attention. This supports a model of shared genetic influence between schizotypy and cognitive functions impaired in schizophrenia.

The Schizotypal Personality Questionnaire - Child (SPQ-C): Psychometric properties and relations to behavioral problems with multi-informant ratings

The Schizotypal Personality Questionnaire (SPQ) is one of the most widely used screening tools for schizotypy in adults. The Schizotypal Personality Questionnaire-Child version (SPQ-C) was recently developed to assess schizotypy in children and has a similar three-factor structure to the adult SPQ (i.e., Cognitive-Perceptual, Interpersonal-Affective, and Disorganization). However, few studies to date have reported on the psychometric properties and the usefulness of the SPQ-C in Eastern populations, including Mainland China. This study presents the first psychometric assessment of the Chinese SPQ-C in Mainland China. Exploratory factor analysis and confirmatory factor analysis were used to assess the factor structure of the SPQ-C in 1668 children (M = 12.10, SD = 0.60 years) from the China Jintan Child Cohort Study. Our findings document a three-factor structure and partial measurement invariance across residential location and gender, replicating the psychometric properties of the SPQ-C in English. The Chinese SPQ-C further correlates with standard behavioral problems (i.e., Child Behavior Checklist, Youth Self-Report and Teacher Report Form), demonstrating construct validity and utility as a child psychopathology assessment tool. Our findings provide the first robust psychometric evidence for a three-factor structure of the Chinese SPQ-C in a large Mainland Chinese sample, and suggest that the SPQ-C is suitable as a screening tool for schizotypy in community children who may be at risk for behavioral problems and later psychosis.

Exploratory Graph Analysis of the Multidimensional Schizotypy Scale

The present study examined the dimensional structure underlying the Multidimensional Schizotypy Scale (MSS) and its brief version (MSS-B). We used Exploratory Graph Analysis (EGA) to evaluate their dimensional structure in two large, independent samples (n = 6265 and n = 1000). We then used Confirmatory Factor Analysis (CFA) to compare the fit of the theoretical dimensions with the EGA dimensions. For the MSS, EGA identified four dimensions: positive schizotypy, two dimensions of negative schizotypy (affective and social anhedonia), and disorganized schizotypy. For the MSS-B, EGA identified three dimensions, which corresponded to the theorized positive, negative, and disorganized dimensions. Based on the MSS's EGA dimensions, we also estimated a four-factor model for the MSS-B. The CFA comparison found that the four-factor model fit significantly better than the theoretical three-factor model for both the MSS and MSS-B, providing support for the theoretical model and offering a more nuanced interpretation of the negative schizotypy factor. In addition, EGA also revealed that the positive and negative schizotypy dimensions of the MSS and MSS-B might be mediated by the disorganized dimension. Our findings offer new implications for future research on the MSS and MSS-B dimensions that may provide differential associations with interview and questionnaire measures.

Spirituality, dimensional autism, and schizotypal traits: The search for meaning

The relationships of spirituality with human social cognition, as exemplified in autism spectrum and schizophrenia spectrum cognitive variation, remain largely unstudied. We quantified non-clinical levels of autism spectrum and schizotypal spectrum traits (using the Autism Quotient and the Schizotypal Personality Questionnaire-Brief Revised) and dimensions of spirituality (using the Hardt Spirituality Questionnaire) in a large sample of undergraduate students. We tested in particular the hypothesis, based on the diametrical model of autism and psychosis, that autism should be negatively associated, and positive schizotypal traits should be positively associated, with spirituality. Our primary findings were threefold. First, in support of the diametric model, total Spirituality score was significantly negatively correlated with total Autism Quotient score, and significantly positively correlated with Positive Schizotypal traits (the Schizotypal Personality Cognitive-Perceptual subscale), as predicted. Second, these associations were driven mainly by opposite patterns regarding the Search for Meaning Spirituality subscale, which was the only subscale that was significantly negatively associated with autism, and significantly positively associated with Positive Schizotypal traits. Third, Belief in God was positively correlated with Positive Schizotypal traits, but was uncorrelated with autism traits. The opposite findings for Search for Meaning can be interpreted in the contexts of well-supported cognitive models for understanding autism in terms of weak central coherence, and understanding Positive Schizotypal traits in terms of enhanced salience.

Early maladaptive schemas in patients with schizophrenia and non-patients with high and low schizotypal traits and their differences based on depression severity

BACKGROUND

The aims of this study were to predict positive and negative symptoms of psychosis via early maladaptive schemas (EMSs) in patients with schizophrenia (SZ); to compare EMSs among SZ patients, non-patients with high schizotypal traits, and non-patients with low schizotypal traits; and to compare EMSs among subgroups concerning depression severity.

METHODS

We applied three groups of participants including SZ patients (n = 105), non-patients with low schizotypal traits (n = 90), and non-patients with high schizotypal traits (n = 90). Participants completed the Young Schema Questionnaire-Short Form (YSQ-SF), the Positive and Negative Syndrome Scale (PANSS), the Schizotypal Personality Scale (STA), and the Beck Depression Inventory-II (BDI-II).

RESULTS

The results indicated that the mistrust/abuse and social isolation schemas were significant predictors of positive and negative symptoms in SZ patients respectively. SZ patients and non-patients with high schizotypal traits exceeded non-patients with low schizotypal traits on all EMSs. There were no differences between SZ patients and non-patients with high schizotypal traits regarding EMSs. In the subgroups with high depression, SZ patients showed higher levels of EMSs than non-patients with low and high schizotypal traits. In the subgroups with low depression, both SZ patients and non-patients with high schizotypal traits had higher scores on EMSs than non-patients with low schizotypal traits.

CONCLUSION

The findings suggest that mistrust/abuse and social isolation may be specific to psychosis symptoms. Also, SZ and schizotypal traits may overlap in relation to EMSs. In addition, the activated EMSs may contribute to high depression in SZ.

Beyond Clinical High-Risk State for Psychosis: The Network Structure of Multidimensional Psychosis Liability in Adolescents

OBJECTIVES

The main goal of the present study was to analyze the network structure of schizotypy dimensions in a representative sample of adolescents from the general population. Moreover, the network structure between schizotypy, mental health difficulties, subjective well-being, bipolar-like experiences, suicide ideation and behavior, psychotic-like experiences, positive and negative affect, prosocial behavior, and IQ was analyzed.

METHOD

The study was conducted in a sample of 1,506 students selected by stratified random cluster sampling. The Oviedo Schizotypy Assessment Questionnaire, the Personal Wellbeing Index-School Children, the Paykel Suicide Scale, the Mood Disorder Questionnaire, the Strengths and Difficulties Questionnaire, the Prodromal Questionnaire-Brief, the Positive and Negative Affect Schedule for Children Shortened Version, and the Matrix Reasoning Test were used.

RESULTS

The estimated schizotypy network was interconnected. The most central nodes in terms of standardized Expected Influence (EI) were 'unusual perceptual experiences' and 'paranoid ideation'. Predictability ranged from 8.7% ('physical anhedonia') to 52.7% ('unusual perceptual experiences'). The average predictability was 36.27%, implying that substantial variability remained unexplained. For the multidimensional psychosis liability network predictability values ranged from 9% (estimated IQ) to 74.90% ('psychotic-like experiences'). The average predictability was 43.46%. The results of the stability and accuracy analysis indicated that all networks were accurately estimated.

CONCLUSIONS

The present paper points to the value of conceptualizing psychosis liability as a dynamic complex system of interacting cognitive, emotional, behavioral, and affective characteristics. In addition, provide new insights into the nature of the relationships between schizotypy, as index of psychosis liability, and the role played by risk and protective factors.

Schizotypy and mentalizing: An fMRI study

INTRODUCTION

Schizotypy is a personality trait characterized by subclinical schizophrenia symptoms. Individuals with schizophrenia typically display behavioral mentalizing deficits and altered neural correlates during mentalizing. While schizotypy has been inconsistently related to behavioral mentalizing skills, its neural correlates of mentalizing are understudied so far. With this study we tested the association between schizotypy traits in healthy subjects and mentalizing-related neural correlates to provide new insights into neural processes associated with subclinical schizophrenia traits.

METHODS

Brain activation was measured using fMRI during an interactive mentalizing paradigm (Prisoner's Dilemma Game) in 164 healthy subjects. The Schizotypal Personality Questionnaire (SPQ-B) was administered to assess the three dimensions of schizotypy, i.e., cognitive-perceptual, interpersonal and disorganized.

RESULTS

We found that interpersonal schizotypy was significantly negatively correlated with brain activation in bilateral precunei and right caudate nucleus (among others) during mentalizing. By contrast, disorganized schizotypy was significantly positively correlated with mentalizing-associated neural activation in right precuneus, left middle cingulate cortex and right cerebellar hemisphere. No significant associations for cognitive-perceptual schizotypy and the SPQ-B total score were found.

DISCUSSION

Our study showed that interpersonal and disorganized schizotypy are associated with neural correlates of mentalizing in brain regions that are involved in self-processing and mentalizing. These brain regions have also been linked to mentalizing in schizophrenia.

A reassessment of the higher-order factor structure of the German Schizotypal Personality Questionnaire (SPQ-G) in German-speaking adults

The Schizotypal Personality Questionnaire (SPQ) is a widely-used self-report instrument for the assessment of schizotypal personality traits. However, the factor structure of scores on English and non-English translations of the SPQ has been a matter of debate. With little previous factorial evaluation of the German version of the SPQ (SPQ-G), we re-assessed the higher-order factor structure of the measure. A total of 2,428 German-speaking adults from Central Europe (CE) and the United Kingdom (UK) completed the SPQ-G. Confirmatory factor analysis - testing proposed 2-, 3-, and 4-factor models of SPQ-G scores - indicated that the 4-factor solution had best fit. Partial measurement invariance across cultural group (CE and UK) and sex was obtained for the 4-factor model. Further analyses showed CE participants had significantly higher scores than UK participants on one schizotypal facet. These results suggest that scores on the SPQ-G are best explained in terms of a higher-order, 4-factor solution in German migrant and non-migrant adults.

Comparisons of schizotypal traits across 12 countries: Results from the International Consortium for Schizotypy Research

BACKGROUND

Schizotypal traits are expressions of underlying vulnerability to psychotic disorders which have a potential impact on mental health status, neurocognition, quality of life, and daily functioning. To date, little research has examined epidemiologic landscape of schizotypal traits at the cross-national level. Our aim was to study the expression of schizotypal traits by sex, age, and country in a combined sample gathered from 12 countries.

METHODS

A total of 27,001 participants completed the Schizotypal Personality Questionnaire (SPQ). The mean age of participants was 22.12 (SD=6.28); 37.5% (n=10,126) were males.

RESULTS

Schizotypal traits varied according to sex, age, and country. Females scored higher than males in the positive dimension, whereas males scored higher in the disorganization dimension. By age, a significant decrease in the positive schizotypal traits was observed. Epidemiological expression of schizotypal traits varied by country. Moreover, several interactions by sex, age, and country were found.

CONCLUSIONS

This pattern is similar to those found in patients with psychosis and psychotic-like experiences. These findings provide new insights and the opportunity to explore the phenotypic expression of schizotypal traits at cross-national level.

The factor structure of the short form of the Wisconsin schizotypy scales

The Chapman psychosis-proneness scales-also known as Wisconsin schizotypy scales (WSS)-are among the most used tools to measure schizotypy. The factor structure of the short-form WSS was investigated in a mixed sample of patients with chronic mental disorders and of healthy subjects from the general population. One hundred patients with a chronic mental disorder were enrolled over a 6-month period. For each patient, two controls of same sex and similar age (±5 years) were enrolled; 131 accepted to take part in the study. The unidimensional, the correlated four-factor, the second-order two-factor models, and the bifactor model with two or four orthogonally independent factors of the short-form WSS were tested with confirmatory factor analysis. Good reliability of the short-form WSS was confirmed, as its capacity of differentiating people with and without schizotypy. The bifactor models were superior to other models. However, in both bifactor models the explained common variance (ECV) attributable to the general factor and the percentage of uncontaminated correlations (PUC) were too low to use a general summary score as a measure of a single latent schizotypy variable. Symptoms scores derived from the short-form WSS can be better appreciated within a multidimensional model of schizotypy.