Moderately Eccentric: Evidence for Dimensionality in the Latent Structure of Schizotypal Personality Features

The authors investigated the latent structure of schizotypal personality features using taxometric analysis in a large sample of individuals from clinical and nonclinical populations. A total of 7,072 community adults and 270 psychiatric patients participated in the study by responding to the eccentricity, distrust, and isolation scales from the Dimensional Clinical Personality Inventory (IDCP). Data were analyzed using three different taxometric techniques, MAMBAC, MAXEIG, and L-Mode. The indicators proved valid for the taxometric analysis (d ≥ 1.25). The comparison curve fit index (CCFI) coefficients from the three methods used were close to zero, and the average CCFI was lower than .40, clearly indicating a dimensional structure for schizotypal personality features. These findings suggest that schizotypal personality traits occur in levels, with no evidence of any natural boundary between clinical and nonclinical manifestations. Results from other studies that were consistent with a categorical structure may be due to methodological weaknesses.