Studies of at least 10 participants with borderline personality disorder (diagnosed according to the Diagnostic and Statistical Manual of Mental Diseases) who were treated with dialectical behaviour therapy were eligible for inclusion in the review. Dialectical behaviour therapy was described as specified in the dialectical behaviour therapy manual (Linehan 2003) using the four components: individual therapy, group format, training consultation team and telephone or staff coaching. Alternatively dialectical behaviour therapy could be as described in the in-patient dialectical behaviour therapy programmes (Swenson 2001). Outcomes on suicidal behaviours and self-injury were eligible for inclusion.
The included studies compared dialectical behaviour therapy to the treatments: supportive treatment, transference-focused psychotherapy, community therapy by experts, therapy as usual, comprehensive validation therapy (with and without 12-step therapy) and general psychiatric management. Most studies were conducted in outpatients; four studies were conducted on an in-patient basis. Individual patient exclusion criteria varied between the included studies. Patients were generally excluded from the studies if they had conditions of schizophrenia, bipolar I disorder, substance abuse, mental retardation, acute psychosis/psychotic disorder and seizure disorder (further details reported in the review). Where reported, the included studies comprised mostly women (87.5% to 100%). Mean age of participants ranged from 26.7 years to 36.35 years. Outcomes, including drop-outs, were assessed at different time intervals post-intervention dependant on the individual study; they were usually followed up for at least 12 months (range three months to 30 months).
The authors did not state how many reviewers performed the study selection.