Abstract: | The Borderline Personality Disorder Severity Index-IV-adolescent and parent versions (BPDSI-IV-ado/p) are DSM-IV based semi-structured interviews for the assessment of the severity of symptoms of borderline personality disorder (BPD) in adolescents. The present study evaluates the psychometric properties of the BPDSI-IV-ado/p. The interviews were administered to 122 adolescents, aged 14-19 years and their parents/caretakers who were referred to mental health centres for emotion regulation problems, and to 45 healthy controls. The interrater reliability and internal consistency of all nine subscales (following the nine BPD symptoms in DSM-IV) proved to be good to excellent. Discriminant, concurrent, and construct validity were satisfactory. Cut-off scores that optimize sensitivity and specificity were derived. Informant agreement between adolescents and parents/caretakers was modest. The results of this study suggest that the BPDSI-IV adolescent and parent versions are valid and reliable instruments for the assessment of BPD symptom severity in adolescents. |