Validation of the Three-Item Screener for Personality Disorders From the Inventory of Interpersonal Problems (IIP-3)

Abstract
We previously developed a three-item screener for identifying respondents with any personality disorder (PD) using the Inventory of Interpersonal Problems (IIP). The current goal was to examine the convergent validity of the IIP-3 with other PD screeners and diagnostic tools and to investigate its relationship to measures of adult attachment and emotion regulation. The sample consisted of participants from five studies (total N = 852), with data from collateral informants available for a subsample (N = 353). Despite its brevity, the IIP-3 showed moderate to strong relationships with other longer PD screeners, with PD symptom scores from the Structured Interview for DSM-IV Personality (SIDP-IV), and with a global rating of PD severity. It was most sensitive to the stylistic aspects of PD typical of the traditional DSM cluster B (dramatic, expressive) PDs. These results emerged with data from both participants and informants, although correlations using informant data were generally smaller.