The heterogeneous structure of schizotypal personality disorder: item-level factors of the Schizotypal Personality Questionnaire and their associations with obsessive-compulsive disorder symptoms, dissociative tendencies, and normal personality

Abstract

A. Raine et al.'s (1994) 3-factor scheme is currently the most widely accepted model of schizotypal personality disorder (SPD). Factor analytic studies of the Schizotypal Personality Questionnaire (SPQ; A. Raine, 1991) subscales, which represent the 9 Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria for SPD, have provided the model's primary support. The use of only 9 modeled variables, however, limits the number of factors that can be extracted. To explicate this structure more fully, the authors conducted item-level factor analyses of the SPQ in a large student sample that completed the instrument twice within a 2-week interval. The authors' analyses failed to support either the 3-factor model of SPD or the 9 existing DSM-based subscales of the SPQ. Instead, 5 replicable dimensions emerged that capture recurrent symptom pairings found in the broader SPD literature: Social Anhedonia, Unusual Beliefs and Experiences, Social Anxiety, Mistrust, and Eccentricity/Oddity. These factors are only weakly correlated with each other and show differential correlational patterns with the Big Five personality traits, dissociative tendencies, and symptoms of obsessive-compulsive disorder. Moreover, they are congruent with dimensional models of personality psychopathology. Implications for SPD in DSM-V are discussed.