Schizotypal Personality Disorder in the Alternative Model for Personality Disorders

Schizotypal personality disorder (SPD) first appeared in the American Psychiatric Association diagnostic nosology in 1980, although its roots stretch back more than 100 years under labels such as borderline, ambulatory, and latent schizophrenia. SPD is unique in that it is conceptualized both as stable personality pathology and also as a milder manifestation of schizophrenia-spectrum psychopathology. The categorical operationalization of SPD has remained largely unchanged for the last 40 years, with emphasis on interpersonal deficits, cognitive and perceptual distortions, and odd and eccentric behaviors. The alternative model for personality disorders (AMPD) retained many of the aspects of SPD while offering a hybrid model that includes both disturbances in personality functioning and specific pathological personality traits. The present review examined the empirical literature on the success of the AMPD model in capturing SPD. Although research specifically examining AMPD SPD is limited, there is converging evidence that the six trait facets proposed for the AMPD SPD provide good coverage of SPD and correspond closely to criterion counts from the categorical SPD diagnosis. Furthermore, most studies find that the inclusion of additional facets not proposed for SPD do not account for appreciable variance. However, SPD offers a rather heterogeneous construct, and future studies should consider whether specifying positive, negative, and disorganized traits within the disorder might improve the clarity of the diagnosis.