A time series evaluation of the treatment of histrionic personality disorder with cognitive analytic therapy

The central aim of this study was to assess the effectiveness of cognitive analytic therapy (CAT) with a patient presenting with Histrionic Personality Disorder (HPD). The methodology employed an A/B single case time-series experimental design, with additionally 6 months of continuous follow-up in the experimental measures. Five HPD experimental variables were collected on a daily basis, creating 357 days of continual data for analysis, across various phases of assessment baseline (A), treatment (B) and follow-up. The therapy contract was 24 sessions of CAT, with 4 additional follow-up sessions, spread over the 6-month's post-therapy period. Three out of the five HPD experimental variables (focus on physical appearance, emptiness and child inside) displayed statistically significant phase of treatment effects. Graphing of such data indicated that a 'sudden deterioration' occurred at the point of termination, with eventual recovery and maintenance of the progress made during the intervention. A battery of validated clinical measures were also completed at assessment, termination and final follow-up sessions; analysis of the general measures illustrated clinically significant change, indexing personality integration and reductions to depression. The study is discussed in terms of methodological and clinical limitations, the central importance of process issues and effective termination in HPD, plus the potential utility of CAT in the treatment of HPD presentations.