Frequency of Personality Disorders in Two Age Cohorts of Psychiatric Inpatients

OBJECTIVE: The authors examined the frequency of DSM-III-R personality disorders in adolescent and young adult psychiatric inpatients. METHOD: Structured diagnostic interviews were reliably performed with a series of 255 consecutively admitted inpatients (138 adolescents and 117 young adults). RESULTS: Most personality disorders were diagnosed in similar frequencies in the two study groups. Passive-aggressive personality disorder was diagnosed with lower frequency and dependent personality disorder with higher frequency in the young adult than in the adolescent group. CONCLUSIONS: The isomorphism of relative frequencies among psychiatric inpatients suggests that what is seen in adolescents are valid forms of most adult personality disorders. (Am J Psychiatry 1998; 155:140–142)