Treatment of personality disorder. 
The evidence base for the effective treatment of personality disorders is insufficient.  Most of the existing evidence on personality disorder is for the treatment of borderline personality disorder, but even this is limited by the small sample sizes and short follow-up in clinical trials, the wide range of core outcome measures used by studies, and poor control of coexisting psychopathology.  Psychological or psychosocial intervention is recommended as the primary treatment for borderline personality disorder and pharmacotherapy is only advised as an adjunctive treatment.  The amount of research about the underlying, abnormal, psychological or biological processes leading to the manifestation of a disordered personality is increasing, which could lead to more effective interventions.  The synergistic or antagonistic interaction of psychotherapies and drugs for treating personality disorder should be studied in conjunction with their mechanisms of change throughout the development of each.