Abstract
Cluster A personality disorders (PD), including schizotypal personality disorder (SPD), paranoid personality disorder (PPD), and schizoid PD, are marked by odd and eccentric behaviors, and are grouped together because of common patterns in symptomatology as well as shared genetic and environmental risk factors. The DSM-IV-TR describes personality disorders as representing stable and enduring patterns of maladaptive traits, and much of what is understood about Cluster A personality disorders in particular stems from research with adult populations. Less in known about these disorders in children and adolescents, and controversy remains regarding diagnosis of personality disorders in general in youth. The current paper reviews the available research on Cluster A personality disorders in childhood and adolescence; specifically, we discuss differentiating between the three disorders and distinguishing them from other syndromes, measuring Cluster A disorders in youth, and the nature and course of these disorders throughout childhood and adolescence. We also present recent longitudinal data from a sample of adolescents diagnosed with Cluster A personality disorders from our research laboratory, and suggest directions for future research in this important but understudied area.