The Treatment of Dissociative Identity Disorder with Cognitive Analytic Therapy: Experimental Evidence of Sudden Gains

ABSTRACT

The central aim of this study was to assess the effectiveness of cognitive analytic therapy (CAT) with a patient presenting with DID. The methodology employed an A/B single case experimental design with six-months continuous follow-up in seven experimental measures. A and B represent the assessment of seven dissociative experimental variables under two conditions: baseline (A) and treatment (B). Treatment consisted of 24 sessions of CAT with four follow-up sessions, which is standard within the CAT model for personality disorder patients. A battery of measures of general psychological functioning was also completed at assessment, termination, and follow-up. During treatment the intensity of a range of dissociative symptoms was observed to be reduced, with sudden gains evident due to specific CAT interventions in specific dissociative symptoms. The long-term effectiveness of the intervention was established by the illustration of either continued stability or continued improvement in experimental variables across the follow-up period. Analysis of the general measures illustrates clinically significant change across a variety of robust psychometric measures. The study illustrates the utility of single-case approaches with dissociative disorders and the potential for utilizing CAT generally with such presentations.

KEYWORDS:

• Dissociative identity disorder
• single case experimental design
• cognitive analytic therapy
• treatment outcome