Effectiveness of Predominantly Group Schema Therapy and Combined Individual and Group Schema Therapy for Borderline Personality Disorder: A Randomized Clinical Trial

Abstract

Importance: Schema therapy (ST), delivered either in an individual or group format, has been compared with other active treatments for borderline personality disorder (BPD). To our knowledge, the 2 formats have not been compared with treatment as usual (TAU) or with each other. Such comparisons help determine best treatment practices.

Objective: To evaluate whether ST is more effectively delivered in a predominantly group or combined individual and group format and whether ST is more effective than optimal TAU for BPD.

Design, setting, and participants: In this multicenter, 3-arm randomized clinical trial conducted at 15 sites in 5 countries (Australia, Germany, Greece, the Netherlands, and the UK), outpatients aged 18 to 65 years who had BPD were recruited between June 29, 2010, and May 18, 2016, to receive either predominantly group ST (PGST), combined individual and group ST (IGST), or optimal TAU. Data were analyzed from June 4, 2019, to December 29, 2021.

Interventions: At each site, cohorts of 16 to 18 participants were randomized 1:1 to PGST vs TAU or IGST vs TAU. Both ST formats were delivered over 2 years, with 2 sessions per week in year 1 and the frequency gradually decreasing during year 2. Assessments were collected by blinded assessors.

Main outcomes and measures: The primary outcome was the change in BPD severity over time, assessed with the Borderline Personality Disorder Severity Index (BPDSI) total score. Treatment retention was analyzed as a secondary outcome using generalized linear mixed model survival analysis.

Results: Of 495 participants (mean [SD] age, 33.6 [9.4] years; 426 [86.2%] female), 246 (49.7%) received TAU, 125 (25.2%) received PGST, and 124 (25.0%) received IGST (1 of whom later withdrew consent). PGST and IGST combined were superior to TAU with regard to reduced BPD severity (Cohen d, 0.73; 95% CI, 0.29-1.18; P < .001). For this outcome, IGST was superior to TAU (Cohen d, 1.14; 95% CI, 0.57-1.71; P < .001) and PGST (Cohen d, 0.84; 95% CI, 0.09-1.59; P = .03), whereas PGST did not differ significantly from TAU (Cohen d, 0.30; 95% CI, -0.29 to 0.89; P = .32). Treatment retention was greater in the IGST arm than in the PGST (1 year: 0.82 vs 0.72; 2 years: 0.74 vs. 0.62) and TAU (1 year: 0.82 vs 0.73; 2 years: 0.74 vs 0.64) arms, and there was no significant difference between the TAU and PGST arms (1 year: 0.73 vs 0.72; 2 years: 0.64 vs 0.62).

Conclusions and relevance: In this randomized clinical trial, IGST was more effective and had greater treatment retention compared with TAU and PGST. These findings suggest that IGST is the preferred ST format, with high retention and continuation of improvement in BPD severity after the completion of treatment.

Trial registration: trialregister.nl Identifier: NTR2392.

Conflict of interest statement

Conflict of Interest Disclosures: Dr Arntz reported receiving grants from the Netherlands Organization for Health Research and Development and Netherlands Foundation for Mental Health, and receiving other grants outside the submitted work from Netherlands’ Organization for Scientific Research (NWO), Netherlands Organization for Health Research and Development (ZONMW), Stichting Achmea Gezondheidszorg, CZ Fonds, Stichting Volksbond Rotterdam, and Stichting tot Steun VCVGZ; receiving royalties (paid to the university) from Academic Press, American Psychological Association Press, Beltz, Bohn Stafleu van Loghum, Boom Uitgevers, Cambridge University Press, Context Press, Guilford, De Tijdstroom, Oxford University Press, SAGE Publications, Uitgeverij Nieuwezijds, Wiley; providing workshops and lectures on cognitive behavioral therapy (CBT), imagery rescripting, personality disorders, schema therapy, and small-scale research in clinical practice (remuneration to the university) for the BABCP, Bulgarian Association for CBT, Clinical Academic Group for Psychotherapy Denmark, Danish Competence Centre for Psychotherapy, EABCT, ECNP, ESSPD, Estonian CBT Association, German Psychosomatic Congress, GGZ InGeest, Greek CBT Association, ICCP, Institut für Schematherapie Frankfurt, ISC International, ISSPD, ISST, Jellinek, Kenniscentrum Persoonlijkheidsstoornissen, Leiden University Medical Center, Lemion, Moroccan Association of CBT, Norwegian Psychological Association, Parnassia/PsyQ, Polish Association for Cognitive and Behavioural Therapies, Portuguese Association of Behaviour Therapy, Psyflix, SCEM, Scuole APC-SPC-SICC-IGB-AIPC, Tunisian Association of CBT, Turkish Association for Cognitive & Behavioral Psychotherapies, Ukraine Association for CBT, Ukraine Institute for CBT, University of Bordeaux, VGCT, VST, WCBCT; supervising research at the mental health institute PsyQ (remuneration to the University of Amsterdam); and being chair of the board of the PDO foundation, North Holland postgraduate training institute (unpaid). Dr Jacob reported receiving grants from the Else Kröner Fresenius-Stiftung; receiving grants from the German Research Foundation outside the submitted work; receiving personal fees for books from Beltz, Elsevier, Hogrefe, and Klett-Cotta; and receiving personal fees for workshops from Institute for Schema Therapy Hamburg, Institute for Schema Therapy Freiburg, Institute for Schema Therapy Cologne, Institute for Schema Therapy Bochum, Institute for Schema Therapy Berlin, CIP Akademie Munich, VTF Falkenried Hamburg, and NeST Institute for Schema Therapy Nuremberg. Dr Lee reported conducting training through Psychology Training; conducting workshops as part of the Australian Psychological Society Clinical College, EMDR international Association, Rural Doctors Association of Australia, International Society of Traumatic Stress Studies; having adjunct positions at the University of Western Australia and Murdoch University; receiving a Rotary Mental Health Grant for the current project and receiving a grant from Ramsay Health for research on depression; and being a board director for the Australian Psychological Society (paid) and for the WA PTSD Association (unpaid). Dr Brand-de Wilde reported having been employed at de Viersprong; having a (paid) freelance working affiliation with Jeugdhulp Friesland; being head of the psychotherapy training of RINO Amsterdam (paid); having an unpaid affiliation with the University of Amsterdam; being co-owner of Schematherapie in Bedrijf; being Managing Director of Treatment Affairs at Jeugdhulp Friesland; receiving royalties from Guilford Publications and Bohn Stafleu van Loghum and Boom Uitgevers; and receiving personal fees from providing lectures on (group) schema therapy, imagery rescripting, and personality disorders for EABCT, ISST, VGCT, VST, and Jeugdhulp Friesland. Dr Fassbinder reported receiving grants outside the submitted work from the Else Kröner-Fresenius-Stiftung, the University of Lübeck, and Addisca GmbH; receiving royalties from Beltz Verlag and Elsevier Books; receiving personal fees from supervision in schema therapy and group schema therapy and from workshops and presentations on CBT, imagery rescripting, personality disorders, schema therapy, and behavioral activation for Ausbildungsinstitut für Verhaltenstherapie und Verhaltensmedizin Hannover, Arbeitsgemeinschaft Wissenschaftliche Psychotherapie Berlin, the DGPPN, IPAM Marburg, IFT-Nord Institut für Therapie- und Gesundheitsforschung gemeinnützige GmbH Kiel, IPP Halle, Institut für Schematherapie Hamburg, Institut für Schematherapie Köln, Institut für Schematherapie Berlin, Oberberg Kliniken, and the WCBCT; and being co-chair of the Deutscher Fachverband für Verhaltenstherapie eV (unpaid). Mr Harper reported presenting workshops and trainings for Bradford District Care NHS Foundation Trust. Dr Lavender reported receiving royalty fees from Oxford University Press and Sage Publications outside the submitted work; receiving personal fees from teaching workshops on personality disorders from the Institute of Psychiatry, Psychology and Neuroscience and from Camden and Islington NHS Trust. Dr Lockwood reported presenting webinars for Schema Therapy Space and the Center for Cognitive Therapy, Russia on schema therapy (paid) and receiving personal fees for providing trainings in schema therapy for the Castle Wood Eating Disorders Treatment Center in California and for the State of Nebraska Department of Correctional Services. Dr Malogiannis reported receiving fees for providing workshops, training, and/or supervision for the Greek Society of Schema Therapy, the Institute of Behaviour Research and Therapy of Athens, Greece, and the S.A. (Limited Liability Company) of Cognitive and Behaviour Therapy Education, Athens, Greece, and receiving financial support for the study from the Institut für Verhaltenstherapie Ausbildung Hamburg. Dr Ruths reported being director of Elector Palatinate Ltd (paid); teaching at the Institute for Psychiatry Psychology and Neuroscience, King’s College London (unpaid); and receiving personal fees for teaching CBT including schema therapy for Solomons Tunbridge Wells (UK), Global Mental Health Institute for Public Health Heidelberg (Germany), and OdNova Gabinety Psychoterapeutyczne spółka cywilna (Poland). Dr Schweiger reported receiving royalty fees from Beltz, Herder, Hogrefe, Kohlhammer, and Springer; fees for workshops for Institutes associated with the Deutsche Fachverband für Verhaltenstherapie on psychotherapy topics; and being Vice President of the Deutsche Fachverband für Verhaltenstherapie (no honorarium). Ms Shaw and Dr Farrell reported being co-directors of the Schema Therapy Institute Midwest–Indianapolis; providing training and supervision for professional fees for the National University of Ireland, Idaho State Drug Court Treatment Program, Spalding University Forensic Track, Murdoch University, Perth, Australia, de Viersprong PD Institute, Clienia Littenheid Switzerland, IVAH Hamburg, University of Indianapolis, IPST_MZ Institute, Schema Therapy Institute New York, Van Genderen Opleidingen, Singapore Prison System, New Jersey Schema Therapy Institute, Leiden University, Swedish Institute CBT & ST, Stockholm, Istituto di Scienze Cognitive, Moscow Institute of Schema Therapy, St. Petersburg ST Institute, Greek Schema Society, Danish ST Institute, Norwegian STI, London Schema Therapy Institute, Japanese Society Schema Therapy, Schema Therapy Institute Australia, Schema Therapy Institute Hamburg, Schema Therapy Institute Frankfurt, Schema Therapy Institute Prague, Hungarian Schema Therapy Society; receiving honoraria for presentations from the International Society of Schema Therapy and Australian Psychological Association; and receiving royalties from Wiley-Blackwell and Guilford Press for writing books. Ms. Shaw reported receiving fees from Groningen University for supervising a grant-funded study. Dr Farrell reported receiving an honorarium as a visiting professor at St. Petersburg Polytechnical University. Dr Zarbock reported receiving personal fees from Beltz Verlag for publications, and from IVAH gGmbH (Germany), DGPPN Berlin (Germany), ISST St. Petersburg (Russia) for teaching. No other disclosures were reported.

Figures

Figure 1.. CONSORT Diagram

IGST indicates combined individual and group schema therapy; PGST, predominantly group schema therapy; and TAU, (optimal) treatment as usual.

Figure 2.. Borderline Personality Disorder Severity Index (BPDSI) Scores and Duration of Treatment Retention

A, Estimated marginal means and 95% CIs from the generalized linear mixed model (GLMM) analysis of the total BPDSI scores for the 3 treatment arms. The horizontal line indicates the clinical BPDSI cutoff score of 15, and whiskers indicate 95% CIs. B, Treatment retention by study arm quarterly for 2 years, from the GLMM survival analysis. IGST indicates combined individual and group schema therapy; PGST, predominantly group schema therapy; and TAU, (optimal) treatment as usual.