Validation of the standardised assessment of personality--abbreviated scale in a general population sample

Abstract

Background: Personality disorder (PD) is associated with important health outcomes in the general population. However, the length of diagnostic interviews poses a significant barrier to obtaining large scale, population-based data on PD. A brief screen for the identification of people at high risk of PD in the general population could be extremely valuable for both clinicians and researchers.

Aim: We set out to validate the Standardised Assessment of Personality - Abbreviated Scale (SAPAS), in a general population sample, using the Structured Clinical Interviews for DSM-IV Personality Disorders (SCID-II) as a gold standard.

Method: One hundred and ten randomly selected, community-dwelling adults were administered the SAPAS screening interview. The SCID-II was subsequently administered by a clinical interviewer blind to the initial SAPAS score. Receiver operating characteristic analysis was used to assess the discriminatory performance of the SAPAS, relative to the SCID-II.

Results: Area under the curve for the SAPAS was 0.70 (95% CI = 0.60 to 0.80; p < 0.001), indicating moderate overall discriminatory accuracy. A cut point score of 4 on the SAPAS correctly classified 58% of participants. At this cut point, the sensitivity and specificity were 0.69 and 0.53 respectively.

Conclusion: The SAPAS operates less efficiently as a screen in general population samples and is probably most usefully applied in clinical populations.

Figure 1

Receiver operating characteristic (ROC) curve for Standardised Assessment of Personality – Abbreviated Scale (SAPAS) as a screen for any Structured Clinical Interviews for DSM‐IV Personality Disorder (SCID‐II)

Figure 2

Sensitivity–specificity plot relating Structured Clinical Interviews for DSM‐IV Personality Disorder (SCID‐II) positive diagnosis to total score on the Standardised Assessment of Personality – Abbreviated Scale (SAPAS)