Prevalence
A prevalence estimate for paranoid personality based on a probability subsample from
Part II of the National Comorbidity Survey Replication suggests a prevalence of 2.3%,
while the National Epidemiologic Survey on Alcohol and Related Conditions data suggest
a prevalence of paranoid personality disorder of 4.4%.
Development and Course 
Paranoid personality disorder may be first apparent in childhood and adolescence with
solitariness, poor peer relationships, social anxiety, underachievement in school, hyper-
sensitivity, peculiar thoughts and language, and idiosyncratic fantasies. These children
may appear to be “odd” or “eccentric” and attr act teasing. In clinical samples, this disorder
appears to be more commonly diagnosed in males.
Risk and Prognostic Factors
Genetic and physiological. There is some evidence for an increased prevalence of par-
anoid personality disorder in relatives of probands with schizophrenia and for a more spe-
cific familial relationship with delusional disorder, persecutory type.
Culture-Related Diagnostic Issues
Some behaviors that are influenced by sociocultural contexts or specific life circumstances
may be erroneously labeled paranoid and may ev en be reinforced by the process of clinical
evaluation. Members of minority groups, immi grants, political and economic refugees, or
individuals of different ethnic backgrounds may display guarded or defensive behaviors
because of unfamiliarity (e.g., language barriers or lack of knowledge of rules and regula-
tions) or in response to the perceived neglect or indifference of the majority society. These
behaviors can, in turn, generate anger and fr ustration in those who deal with these indi-
viduals, thus setting up a vicious cycle of mutual mistrust, which should not be confused
with paranoid personality diso rder. Some ethnic groups also display culturally related be-
haviors that can be misinterpreted as paranoid.