Assessing psychotic-like experiences using categorical and metacognitive approaches: A validation of polish self-report measures.

Abstract

Psychotic-like experiences (PLEs) are experiences in the general population that, in their extreme form, are attributed to clinical psychosis. They are correlated with general psychopathology and increased risk of developing psychosis. Previous research show a multitude of measuring tools which most often lack psychometric validation. This study aimed to examine both categorical and metacognitive measures of PLEs. Confirmatory Factor Analysis (CFA) was used in seven online studies with n's ranging from 259 to 6772 to explore factor structures of Prodromal Questionnaire 16 item (PQ-16), Revised Green et al. Paranoid Thoughts Scale (R-GPTS), Multi-Modality Unusual Sensory Experiences Questionnaire (MUSEQ), Beliefs about Paranoia Scale (BAPS) and Interpretation of Voices Inventory (IVI). Additionally, we explored measurement invariance between diagnosed with psychiatric disorders and undiagnosed individuals in PQ-16, R-GPTS and BAPS. We confirmed the factor structures of all questionnaires except IVI. We confirmed configural, threshold and metric measurement invariance in R-GPTS and BAPS and partially PQ-16. The current results demonstrate structural validity and measurement invariance of several categorical and metacognitive measures of PLEs.