BACKGROUND:

Dialectical behaviour therapy (DBT) is widely considered to be a promising treatment for borderline personality disorder (BPD). However, the evidence for its efficacy published thus far should be regarded as preliminary.

AIMS:

To compare the effectiveness of DBT with treatment as usual for patients with BPD and to examine the impact of baseline severity on effectiveness.

METHOD:

Fifty-eight women with BPD were randomly assigned to either 12 months of DBT or usual treatment in a randomised controlled study. Participants were recruited through clinical referrals from both addiction treatment and psychiatric services. Outcome measures included treatment retention and the course of suicidal, self-mutilating and self-damaging impulsive behaviours.

RESULTS:

Dialectical behaviour therapy resulted in better retention rates and greater reductions of self-mutilating and self-damaging impulsive behaviours compared with usual treatment, especially among those with a history of frequent self-mutilation.

CONCLUSIONS:

Dialectical behaviour therapy is superior to usual treatment in reducing high-risk behaviours in patients with BPD.