Does the ICD 10 classification accurately describe subtypes of borderline personality disorder?

The aim of the paper is to explore whether the division of borderline perso nality disorder, as described in the DSM classification, into impulsive and borderline subtypes of emotionally unstable personality disorder in the IC D classification of personality disorder, is a valid division. The self-rep ort questionnaire responses of 288 referrals to a personality disorder serv ice were rated on each of the eight criteria for DSM-III-R diagnosis of bor derline personality disorder. Factor analysis identified two factors; facto r one closely corresponds with the borderline subtype of ICD10, whilst fact or two closely corresponds with the impulsive subtype of ICD10. Criteria co mmon to both factors unstable relationships and identity confusion - were c onsidered core features of borderline personality disorder. The pattern of occurrence of the two factors was similar to the complex binary picture des cribed by ICD10. However there were also differences. Firstly, identity con fusion is found to be a core feature of both our factors, and this does not conform to the restriction of identity confusion to the borderline subtype s in ICD10. Secondly, we found a residual Cool of undifferentiated borderli ne patients and a small group of pure non-impulsive borderline patients who are nor: currently accommodated within the ICD10 emotionally unstable pers onality disorder. We conclude that future classifications of this disorder should accommodate four subtypes, and suggest these subtypes have implicati ons for treatment and further research.