Multiple axis-II diagnoses of personality disorder.
BACKGROUND
Simultaneous diagnosis of more than one personality disorder (PD) has been termed 'comorbidity' or 'co-occurrence' implying that single diagnoses are the norm and multiple diagnoses interesting exceptions. Surveys of PD subjects in fact show 1.5-5.6 diagnoses per subject. Our study explores the hypothesis that multiple PD diagnosis is common and increases with increasingly personality disordered populations.


METHODS
The PDQ-R questionnaire was administered to three UK samples: referrals for specialist PD in-patient treatment (n = 275); high tariff offenders attending a probation centre (n = 57); and undergraduate students (n = 274).


RESULTS
Means of 6.0 (95% CI 5.7-6.3), 4.0 (3.1-5.0) and 3.4 (3.0-3.8) PDQ-R diagnoses per subject were found respectively. High rates of PD diagnosis in individual subjects suggest that multiple diagnosis is the norm rather than the exception.


CONCLUSIONS
Multiple diagnosis of PD is better construed as 'breadth' of psychopathology rather than comorbidity and is a function of sampling frame. High rates of multiple diagnoses question the interpretation of studies of any single PD. The graded construct of 'breadth' of axis-II pathology may further our understanding of PD.
Dolan
B
B
Henderson Hospital, Sutton.
Evans
C
C
Norton
K
K
D000293:Adolescent; D000328:Adult; D000987:Antisocial Personality Disorder / Q000145:classification / Q000175:diagnosis* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010554:Personality Disorders / Q000145:classification / Q000175:diagnosis* / Q000523:psychology; D011329:Prisoners / Q000523:psychology; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data*; D011594:Psychometrics; D012016:Reference Values; D015203:Reproducibility of Results; D013808:Therapeutic Community