Summary: Short-term stability or test-retest reliability of self-reported personality traits is likely to be biased if the respondent is affected by a depressive or anxiety state. However, in some studies, DSM-oriented self-reported instruments have proved to be reasonably stable in the short term, regardless of co-occurring depressive or anxiety disorders. In the present study, we examined the short-term test-retest reliability of a new self-report questionnaire for personality disorder diagnosis (DIP-Q) on a clinical sample of 30 individuals, having either a depressive, an anxiety, or no axis-I disorder. Test-retest scorings from subjects with depressive disorders were mostly unstable, with a significant change in fulfilled criteria between entry and retest for three out of ten personality disorders: borderline, avoidant and obsessive-compulsive personality disorder. Scorings from subjects with anxiety disorders were unstable only for cluster C and dependent personality disorder items. In the absence of co-morbid depressive or anxiety disorders, mean dimensional scores of DIP-Q showed no significant differences between entry and retest. Overall, the effect from state on trait scorings was moderate, and it is concluded that test-retest reliability for DIP-Q is acceptable.
