A proposed solution to past differences in the classification of borderline personality disorder.

Abstract

There has been considerable controversy surrounding the classification of the borderline personality disorder. Investigators disagree whether this illness constitutes an independent phenomenon (4) or is acmally a variant of schizophrenia (5) or major affective disorders ( 1). Despite improvements in diagnostic criteria (2) and validation procedures (3), the boundaries that. distinguish the borderline condition from other psychiatric disorders remain obscure. One methodological obstacle to establishing a consensus regarding borderline personality disorder has been the variety of dependent measures used to test its diagnostic validity. Two recent investigations serve to illustrate this point (6, 7). Both studies employed similar diagnostic groups whose identities were established on five to six different outcome variables. Unfortunately, only one of these variables was comparable across studies. Since outcome consists of more than a single discrete domain (a), it is not surprising that different results were obtained in each study. Pope, et A. (7) found that the borderline disorder was indistinguishable from schizophrenia while McGlashan (6) observed that borderlines were more closely affiliated with major affective disorders. It is clear that identifying a set of outcome measures is a prerequisite to assessing the diagnostic validity of the borderline disorder. This identification can be obtained by performing a multivariate discriminant analysis of outcome scores co achieve sequentially selected variables on the basis of their ability to differentiate groups and eliminate redundant variables that do not contribute to group separation. Such a multivariate approach would establish a statistically valid set of outcome criteria to assess the feasibility of labeling the borderline personality disorder as a separate entity.