ABSTRACT
PURPOSE: This study reviewed the evidence-base status of mentalization-based treatment (MBT), its quality, strengths, and limitations. The aim was to pave the way for further MBT research. METHOD: An electronic database and reference lists search identified MBT outcome papers, and these were systematically reviewed. The quality of the studies and the risk of bias were determined using two validated checklist tools. RESULTS: Twenty-three studies were included in the review. This included nine randomized controlled trials, seven uncontrolled pre- and post-effectiveness studies, three retrospective cohort studies, two uncontrolled randomized trials, and two case studies. The methodological quality of almost half of the papers was assessed as fair (43%), followed by good (34%), poor (17%), and excellent (4%) ratings. Nevertheless, the review identified risk of confounding bias across the majority of studies (60%) and fidelity to treatment was poorly reported in almost half of the studies (47%). Most of the studies focused on borderline personality disorder (BPD), showing positive clinical outcomes for this population but the evidence-base for other presentations was still developing. The treatment of adolescents who self-harm and at-risk mothers in substance abuse treatment showed particularly promising results, as these are client groups that have previously shown limited positive response to psychological interventions. CONCLUSIONS: Mentalization-based treatment is a potentially effective method across a wide range of clinical presentations but further research should focus on increasing the quality and the quantity of the MBT evidence outside the treatment of BPD. PRACTITIONER POINTS: MBT can be a particularly effective intervention for the treatment of adults with a diagnosis of BPD and of adolescents who self-harm and mothers enrolled in substance abuse treatments. MBT can be an effective intervention for depression and eating disorders but the evidence is currently limited. Professionals supporting mothers of children at risk may benefit from receiving training in the principles of MBT.