Measuring pathological traits of the schizotypal personality disorder through the HiTOP model

Schizotypal personality disorder (STPD) is characterized by difficulties in intimate relationships, social and interpersonal deficits, and perceptual distortions. Encompassing this personality disorder and other mental conditions, the Hierarchical taxonomy of psychopathology (HiTOP) is an evidence-based, dimensional model covering pathological traits in its lower range. This study aimed to develop a self-report scale for screening pathological traits of STPD from the perspective of the HiTOP. The sample consisted of 474 Brazilian adults aged 18-70 years who answered the developed scale, the IDCP-STPD, facets of the Personality Inventory for DSM-5 (PID-5), and factors of the Computerized Adaptive Assessment of Personality Disorder Static Form (CAT-PD-SF). The scale was composed of 73 items distributed in two factors. Internal structure reliability was higher than 0.80 for all scores of the scale. The factors showed associations with the expected external measures, and the groups based on the STPD external measures (healthy and pathological) showed big to huge differences. Although initial, our findings suggested the IDCP-STPD as a helpful measure to the clinical context to screen the STPD pathological traits. Moreover, the structure observed for the IDCP-STPD confirms the spectrum level of the HiTOP.