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.

A latent profile analysis of schizotypal dimensions: Associations with psychopathology and personality.

The main goal of the present study was to explore the latent structure of schizotypal traits in non-clinical young adults, and compare the latent profiles in clinical and personality characteristics: mental distress, psychosis-proneness, hypomanic experiences, and anticipatory and consummatory pleasure. A large sample of college students (N =1002; mean age =21.11 years; SD =3.92) were administered the Schizotypal Personality Questionnaire-Brief Revised, the Mood Disorder Questionnaire, the short version of the Oxford-Liverpool Inventory of Feelings and Experiences, the General Health Questionnaire-12, and the Temporal Experience of Pleasure Scale. Using latent profile analysis, four latent classes (LC) were identified: "low schizotypy" (62.4%), "average schizotypy" (17.6%), "interpersonal schizotypy" (17.1%), and "high schizotypy" (2.9%). The "high schizotypy" class scored higher on most psychometric indicators of psychopathology and personality (i.e., mental distress, schizotypy, hypomanic experiences, and anticipatory and consummatory pleasure) relative to other three latent classes. The other three schizotypal latent profiles also varied in terms of these psychopathology and personality factors. The identification of homogeneous subgroups of individuals potentially at-risk for psychosis based on schizotypal latent profiles may improve early identification and prevention efforts aimed at reducing the burden associated with psychotic-spectrum disorders and mental health problems.

Dimensional Structure and Measurement Invariance of the Schizotypal Personality Questionnaire - Brief Revised (SPQ-BR) Scores Across American and Spanish Samples.

The main goal of the present study was to test the measurement equivalence of the Schizotypal Personality Questionnaire - Brief Revised (SPQ-BR) scores in a large sample of Spanish and American non-clinical young adults. The sample was made up of 5,625 young adults (M = 19.65 years; SD = 2.53; 38.5% males). Study of the internal structure, using confirmatory factor analysis (CFA), revealed that SPQ-BR items were grouped in a theoretical internal structure of nine first-order factors. Moreover, three or four second-order factor and bifactor models showed adequate goodness-of-fit indices. Multigroup CFA showed that the nine lower-order factor models of the SPQ-BR had configural and weak measurement invariance and partial strong measurement invariance across country. The reliability of the SPQ-BR scores, estimated with omega, ranged from 0.67 to 0.91. Using the item response theory framework, the SPQ-BR provides more accurate information at the medium and high end of the latent trait. Statistically significant differences were found in the raw scores of the SPQ-BR subscales and dimensions across samples. The American group scored higher than the Spanish group in all SPQ-BR domains except Ideas of Reference and Suspiciousness. The finding of comparable factor structure in cross-cultural samples would lend further support to the continuum model of psychosis spectrum disorders. In addition, these results provide new information about the factor structure of schizotypal traits and support the validity and utility of this measure in cross-cultural research.