Some studies have suggested that borderline personality disorder (BPD) can be diagnosed reliably and have concurrent validity in adolescents (1,2). However, the low rate of persistence and the high rates of BPD comorbidity with other personality disorders in adolescents may suggest that this diagnosis lacks predictive and construct validity in this age group (3–5). Adolescents with personality disorders are nonetheless at elevated risk for major mental disorders during early adulthood (6).

The one study examining BPD prevalence in adolescents found an overall prevalence of about 11% (7). Our study assesses its prevalence in a sample of high school students. To our knowledge, it is the first epidemiological study of BPD in European adolescents.

Method

Sample and Measures

A random sample of 1363 high school students from Toulouse, France, were

Manuscript received March 2001, revised, and accepted September 2001.
¹Professor of Psychology, Université de Toulouse-Le Mirail, Toulouse, France.
²Master of Psychology, Université de Toulouse-Le Mirail, Toulouse, France.
³Lecturer, Université de Toulouse-Le Mirail, Toulouse, France.
⁴Directeur d'Études, Ecoles Pratiques des Hautes Études, Paris, France.
Address for correspondence: Dr H Habrol, 21 rue des Cèdres, 31400 Toulouse, France.
e-mail: chabrol@univ-tlse2.fr

asked to complete a personality questionnaire, the Screening Test for Comorbid Personality Disorders (STCPD) (8). STCPD is a 51-item self-report questionnaire devised to screen for borderline, histrionic, avoidant, and dependent personality disorders. The items were modified to reflect age-appropriate language. Of the 1363 subjects, 1202 (479 boys, 723 girls; mean age 16.6 years, SD 1.6; range 13 to 20) satisfactorily completed the questionnaire. The sex distribution suggested that the sample was not representative; this allowed us to calculate frequency rates only. Students were asked to continue in the study by participating in interviews with master’s level psychology students, and 107 students (34 boys, 73 girls; mean age 16.7 years, SD 1.8; range 14 to 20) volunteered for the interview. We obtained written informed consent. This subsample was comparable to the total sample in terms of age (t = 0.61, df 1307, ns) and sex (P² = 2.31, df 1, ns). These subjects were assessed using the Revised Diagnostic Interview for Borderlines (DIB-R) (9), the reliability and validity of which have been shown in adolescents (10,11). Interviewers were trained to administer and score the DIB-R, and the interviews were audiotaped.

According to DSM-IV guidelines, features must have been present for at least 1 year to be counted. As recommended by the authors, subjects were considered to meet the criteria for BPD if they had a DIB-R score greater than or equal to 8. Interrater reliability was determined by comparing the independent ratings of interviewers with those of an experienced clinician on a random sample of 24 interviews.