Background: The view that severe personality disorder (SPD) is untreatable derives from poor-quality studies of treatment outcome which use indirect measures of SPD pathology. This study evaluates the impact of psychotherapeutic in-patient treatment on core personality disorder symptoms.
Method: 137 SPD patients completed the Borderline Syndrome Index (BSI) on referral and one year post-treatment ('admitted', n = 70) or one year post-referral ('non-admitted', n = 67); 22 of the non-admitted group were refused extra-contractual referral funding for their treatment.
Results: There was a significantly greater reduction in BSI scores in the treated than in the non-admitted group. Changes in BSI scores were significantly positively correlated with length of treatment. Assessment of the reliability and clinical significance of changes in individual subjects showed that the magnitude of this change was reliable and clinically significant in 42.9% of the admitted sample, compared with only 17.9% of the non-admitted sample (18.2% of the unfunded group).
Conclusions: Specialist in-patient treatment is effective in reducing core SPD psychopathology.