EDI Subscales Not Sensitive To Cluster B Disorders

Reprinted from Eating Disorders Review
July/August 2004 Volume 15, Number 4
©2004 Gürze Books

The Eating Disorders Inventory (EDI) is one of the most widely used self-rating questionnaires in research and clinical practice. Its 8 subscales assess cognitive-behavioral symptoms commonly found in persons with eating disorders and psychological correlates or personality characteristics present in, but not exclusive to, eating disorders. According to Swiss researchers, the EDI subscales are generally sensitive to Axis I and some Axis II disorders but not to cluster B personality disorders (Can J Psychiatry 2004; 49:179). Axis I disorders are clinical disorders, while Axis II disorders include personality disorders and mental retardation, for example. Cluster B disorders are characterized by dramatic, narcissistic and hysterical personality traits.

Gabriella Milos, MD, and a team at the University of Zurich studied 67 persons from the eating disorders inpatient unit of the University Hospital, Zurich, 66 psychiatric outpatients, and 31 persons with eating disorders from self-help groups over a 2-year period. As expected, participants with bulimia nervosa had higher scores on the EDI-B subscales than did other persons with anorexia nervosa and eating disorders not otherwise specified. Differences between these diagnostic subgroups in the other EDI subscales were not detectable.

The comorbidity on Axis I and Axis II was high. The most common Axis I disorders were affective, anxiety, and substance-related disorders. For Axis II, the most common were personality disorders of cluster C. Just as has been shown in other research on eating disorders, the authors report that their results show that comorbidity on both Axis I and II was predominantly characterized by anxiety and depression.

When the authors examined personality disorder clusters, similar patterns emerged for cluster A, cluster C, and depressive-negativistic personality disorders. An unexpected finding was the difference in EDI profiles between participants with and without cluster B personality disorders. Only subscale B was associated with the presence of cluster B disorders. According to the authors, overlaps between bulimia nervosa symptoms and symptoms of cluster B personality disorders, including borderline personality disorders, have been pointed out. None of the psychological EDI subscales was sensitive to this cluster.

The authors note that clinicians and researchers using the EDI need to be aware that it is not sensitive for all forms of comorbidity among disorders patients. In addition, those with cluster B disorders may give biased responses on the EDI and other self-report measures.

No Comments Yet

Comments are closed