Latent class analysis of DSM-IV schizotypal personality disorder criteria in psychiatric patients

The aim of the study was to evaluate the latent structure of DSM-IV schizotypal personality disorder (SPD) diagnostic criteria, The sample consisted of 564 consecutively admitted inpatients and outpatients. Exploratory latent class analysis identified a four-class model as the best fitting model for DSM-IV SPD criteria, The first of the SPD latent classes was mainly characterized by odd thinking, inappropriate affect, and interpersonal features; the second class by cognitive/perceptual difficulties; the third class by paranoid features; and the fourth class by absence of SPD features. The conditional probability pattern of the four-class solution could be safely replicated across confounder strata, Unlike previous findings, oddness, aloofness, and social withdrawal, rather than positive symptoms, best characterized SPD even in clinical samples.