Objective: The authors conducted a meta-analysis to address the effectiveness of psychodynamic therapy and cognitive behavior therapy in the treatment of personality disorders.
Method: Studies of psychodynamic therapy and cognitive behavior therapy that were published between 1974 and 2001 were collected. Only studies that 1) used standardized methods to diagnose personality disorders, 2) applied reliable and valid instruments for the assessment of outcome, and 3) reported data that allowed calculation of within-group effect sizes or assessment of personality disorder recovery rates were included. Fourteen studies of psychodynamic therapy and 11 studies of cognitive behavior therapy were included.
Results: Psychodynamic therapy yielded a large overall effect size (1.46), with effect sizes of 1.08 found for self-report measures and 1.79 for observer-rated measures. For cognitive behavior therapy, the corresponding values were 1.00, 1.20, and 0.87. For more specific measures of personality disorder pathology, a large overall effect size (1.56) was seen for psychodynamic therapy. Two cognitive behavior therapy studies reported significant effects for more specific measures of personality disorder pathology. For psychodynamic therapy, the effect sizes indicate long-term rather than short-term change in personality disorders.
Conclusions: There is evidence that both psychodynamic therapy and cognitive behavior therapy are effective treatments of personality disorders. Since the number of studies that could be included in this meta-analysis was limited, the conclusions that can be drawn are only preliminary. Further studies are necessary that examine specific forms of psychotherapy for specific types of personality disorders and that use measures of core psychopathology. Both longer treatments and follow-up studies should be included.