Borderline personality disorder (BPD) is frequently subject to misdiagnosis or underdiagnosis. As a matter of fact, its evaluation poses several challenges, highlighting the importance of having validated evaluation instruments. The Revised Diagnostic Interview for Borderlines (DIB-R) is widely used and recognized for its validity when it comes to assessing the psychopathology of BPD, but, as for now, no French version of the interview exists. The aim of the current work is to validate a French version of the DIB-R.
The sample consists of N = 65 patients with borderline personality disorder (BPD) and N = 57 treatment seeking patients (non-BPD comparison group). For inter-rater reliability, a subsample of N = 84 interviews will be assessed by two raters, n = 47 for the BPD group and n = 37 for the non-BPD comparison group.
To assess reliability, we conducted analyses of internal consistency and inter-rater reliability. The results were good for the overall interview as well as for the four domains of the DIB-R. To assess validity, we calculated the receiver operating characteristic (ROC) curve, sensitivity, specificity, predictive values, convergent and discriminative validity. The optimal cutoff was found to be 7. Regarding convergent validity, we found strong convergence between the Borderline Symptom List (BSL-23) and the DIB-R total score. Additionally, the two groups statistically differed on all the DIB-R scores, which indicates that the interview discriminates between the two groups.
Our results indicate good psychometric properties of the French version of the DIB-R. This has important implications as the interview is useful both in clinical settings and for research purposes. Additionally, the present paper aims to contribute to the more general effort of demonstrating generalizability and transportability of the scale.