Personality disorders in substance abusers: validation of the DIP-Q through principal components factor analysis and canonical correlation analysis.
BACKGROUND
Personality disorders are common in substance abusers. Self-report questionnaires that can aid in the assessment of personality disorders are commonly used in assessment, but are rarely validated.


METHODS
The Danish DIP-Q as a measure of co-morbid personality disorders in substance abusers was validated through principal components factor analysis and canonical correlation analysis. A 4 components structure was constructed based on 238 protocols, representing antagonism, neuroticism, introversion and conscientiousness. The structure was compared with (a) a 4-factor solution from the DIP-Q in a sample of Swedish drug and alcohol abusers (N = 133), and (b) a consensus 4-components solution based on a meta-analysis of published correlation matrices of dimensional personality disorder scales.


RESULTS
It was found that the 4-factor model of personality was congruent across the Danish and Swedish samples, and showed good congruence with the consensus model. A canonical correlation analysis was conducted on a subset of the Danish sample with staff ratings of pathology. Three factors that correlated highly between the two variable sets were found. These variables were highly similar to the three first factors from the principal components analysis, antagonism, neuroticism and introversion.


CONCLUSIONS
The findings support the validity of the DIP-Q as a measure of DSM-IV personality disorders in substance abusers.
Hesse
Morten
M
Aarhus University, Centre for Alcohol and Drug Research, Kobmagergade 26E, 1150 Copenhagen C, Denmark. mortenhesse@crf.dk
D000328:Adult; D015897:Comorbidity; D003431:Cross-Cultural Comparison; D003718:Denmark; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005163:Factor Analysis, Statistical; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D038801:International Classification of Diseases; D008297:Male; D015201:Meta-Analysis as Topic; D015233:Models, Statistical; D010554:Personality Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D010555:Personality Inventory / Q000706:statistics & numerical data*; D025341:Principal Component Analysis; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D011594:Psychometrics; D015203:Reproducibility of Results; D013223:Statistics as Topic; D019966:Substance-Related Disorders / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D013548:Sweden