CAT Evidence base

This is a listing of selected recent research publications or summaries about cognitive analytic therapy since 2014. They are generally written for a professional or academic audience. We are producing some more accessible summary blogs about some of them. If you would like to write a blog about a piece of CAT research, please contact us.


Worsley, J., Young, D., Harrison, P., & Corcoran, R. (2024). Pilot Evaluation of a Remote Psychotherapy Service for Students Who Self-Harm: University–Community Outpatient Psychotherapy Engagement (U-COPE). International Journal of Environmental Research and Public Health, 21(1):103.

Kellett, S., Brown, K., Au-Yeung, S. K., Tew, V., & Parry, G. (2024). Personal reformulation during the clinical associate psychologist apprenticeship: Exploratory mixed methods evaluation. British Journal of Clinical Psychology, 00, 1–14.

Haw, R., Marsden, M., Hartley, S., Turpin, C. and Taylor, P. . (2024), A Brief Cognitive Analytic Therapy–Informed Approach for Young People That Have Self-Injured (CATCH-Y): A Case Series. Clin Psychol Psychother, 31: e2976.


Gaskell, C., Kellett, S., Simmonds-Buckley, M., Curran, J., Hetherington, J., & Delgadillo, J. (2023). Long-term psychotherapy in tertiary care: A practice-based benchmarking study. British Journal of Clinical Psychology, 00, 1– 18.

Kellett, S., Bee, C., Smithies, J., Aahdal, V., Simmonds-Buckley, M., Power, N., Dugen-Williams, C., Fallon, N. & Delgidallo, J. (2023). Cognitive–behavioural versus cognitive–analytic guided self-help for mild-to-moderate anxiety: a pragmatic, randomised patient preference trial. The British Journal of Psychiatry, 223(3):438-445. doi:10.1192/bjp.2023.78

Kellett., S. & Stockton, D. (2023) Treatment of obsessive morbid jealousy with cognitive analytic therapy: a mixed-methods quasi-experimental case study, British Journal of Guidance & Counselling, 51:1, 96-114, DOI: 10.1080/03069885.2021.1929834

Moeini, F.R., Goodarzi, N., Dabbaghi, P., Mohsen A.R., & Ghasemzadeh, M.R. (2023). A randomized controlled trial of cognitive analytic versus compassion-focused therapy for PTSD in Iran-Iraq War Veterans. Journal of Military, Veteran and Family Health 0 0:0

Owen, K., Laphan, A., Gee, B. & Lince, K. (2023) Evaluating cognitive analytic therapy within a primary care psychological therapy service. British Journal of Clinical Psychology, 62(3), 663- 673  This is not currently open access, but the Wiley link below will enable read-only access to the full paper:

Power, N., Kellett, S., & Gaskell, C. (2023). Effectiveness of cognitive analytic therapy for mixed anxiety and depression in the context of borderline traits: A quasi-experimental single case design evaluation. Journal of Psychotherapy Integration, 33(1), 34–46.


Kellett, S., Alhadeff, L., Gaskell, C., & Simmonds-Buckley, M. (2022). Effectiveness of cognitive analytic therapy for bipolar affective disorder: A co-produced single subject cumulative treatment design with extended follow-up (A1/B/A2/C-FU). Psychology and Psychotherapy: Theory, Research and Practice, 95, 621–638.

Mangion G., Simmonds-Buckley M,, Kellett S,. Taylor P,. Degnan A., Humphrey C., Freshwater K., Poggioli M,. Fiorani C.(2022). Modelling Identity Disturbance: A Network Analysis of the Personality Structure Questionnaire (PSQ). International Journal of Environmental Research and Public Health. October 24;19(21):13793. doi: 10.3390/ijerph192113793

Simmonds-Buckley, M., Osivwemu, E-O., Kellett, S., & Taylor, C. (2022)
The acceptability of cognitive analytic therapy (CAT): Meta-analysis and benchmarking of treatment refusal and treatment dropout rates,
Clinical Psychology Review, Volume 96, 102187, ISSN 0272-7358,

Wray, A., Kellett, S., Bee, C., Smithies, J., Aadahl, V., Simmonds-Buckley, M., & McElhatton, C. (2022). The acceptability of cognitive analytic guided self-help in an Improving Access to Psychological Therapies service. Behavioural and Cognitive Psychotherapy, 1-15. doi:10.1017/S1352465822000194


In February 2021 the journal Psychology and Psychotherapy, Theory Research and Practice published a special issue on Cognitive Analytic Therapy: Research Developments and Insights, edited by Peter Taylor and Samantha Hartley. Five of the nine articles are open access. You can see the whole special issue at

and individual papers are included in those listed below.

Balmain, N., Melia, Y., Dent, H. and Smith, K. (2021), A systematic review of service user’s experience of cognitive analytic therapy (CAT). Psychol Psychother Theory Res Pract.

Balmain, N., Melia, Y., John, C., Dent, H. and Smith, K. (2021), Experiences of receiving cognitive analytic therapy for those with complex secondary care mental health difficulties. Psychol Psychother Theory Res Pract.

Easton K, Kellett S, Cooper M, Millings A, Varela J, Parry G
Blending Cognitive Analytic Therapy With a Digital Support Tool: Mixed Methods Study Involving a User-Centered Design of a Prototype App
JMIR Ment Health 2021;8(2):e20213
DOI: 10.2196/20213

Hamilton, Z., Tickle, A., Cooper, H. and Moghaddam, N. (2021), An Evaluation of the Influence of CAT Personal Reformulations on Reflective Capacity in Trainee Clinical Psychologists. Journal of Cognitive Analytic Therapy and Relational Mental Health, (4), 112-132.

Hessels, C.J., Laceulle, O.M., van Dijk, I., and van Aken, M. (2021), A CAT-based early intervention for Borderline Personality Disorder: A Pilot Study. Journal of Cognitive Analytic Therapy and Relational Mental Health, (4), 51-74

Kellett K., & Stockton, D., (2021) Treatment of obsessive morbid jealousy with cognitive analytic therapy: a mixed-methods quasi-experimental case study, British Journal of Guidance & Counselling, DOI: 10.1080/03069885.2021.1929834

Martin, E., Byrne, G., Connon, G. and Power, L. (2021), An exploration of group cognitive analytic therapy for anxiety and depression. Psychol. Psychother. Theory Res. Pract. e12299.

Merzhvynska, M., Simmonds‐Buckley, M., Delgadillo, J. and Kellett, S. (2021), Trajectories of change in the therapeutic alliance during Cognitive Analytic Therapy for depression. Psychol Psychother Theory Res Pract.

Parry, G., Bennett, D., Roth, A.D. and Kellett, S. (2021), Developing a competence framework for cognitive analytic therapy. Psychol Psychother Theory Res Pract.

Priddy, S., Varela, J., and Randall, J. (2021), ‘We’re able to see the smoke’:
Exploring staff experiences of remote cognitive analytic team
formulation within a residential learning disability service. International Journal of Cognitive Analytic Therapy and Relational Mental Health (4), 27-50.

Taylor, P.J. and Hartley, S. (2021), Reformulating the relationship between cognitive analytic therapy and research: Navigating the landscape and exploring new directions. Psychol Psychother Theory Res Pract, 94: 1-7 e12292.

Wakefield, S., Delgadillo, J., Kellett, S., White, S. & Hepple, J. (2021) The effectiveness of brief cognitive analytic therapy for anxiety and depression: A quasi‐experimental case-control study. British Journal of Clinical Psychology. Early View (Open Access)


Baronian, R., & Leggett, S. J. (2020). Brief cognitive analytic therapy for adults with chronic pain: a preliminary evaluation of treatment outcome. British Journal of Pain, 14(1), 57–67.

Hamilton J, Saxon D, Best E, Glover V, Walters SJ, Kerr IB. (2020) A randomized, controlled pilot study of cognitive analytic therapy for stressed pregnant women with underlying anxiety and depression in a routine health service setting. Clin Psychol Psychother. 2020 Sep 30. doi: 10.1002/cpp.2520. Epub ahead of print. PMID: 32997871.

Kellett, S., Bee, C., Aadahl, V., Headley, E., & Delgadillo, J. (2020). A pragmatic patient preference trial of cognitive behavioural versus cognitive analytic guided self-help for anxiety disorders. Behavioural and Cognitive Psychotherapy, 1-8. doi:10.1017/S1352465820000442

Kellett S, Easton K, Cooper M, Millings A, Simmonds-Buckley M, Parry G (2020) Evaluation of a Mobile App to Enhance Relational Awareness and Change During Cognitive Analytic Therapy: Mixed Methods CaseSeries. JMIR Ment Health 2020;7(12): e19888 URL: doi: 10.2196/19888

Kellett, S., & Lees, S. (2020). Quasi-experimental N = 1 evaluation of the effectiveness of cognitive analytic therapy for dependent personality disorder. Journal of Psychotherapy Integration, 30(3), 458–475.


Kellett, S., Ghag, J., Ackroyd, K., Freshwater, K., Finch, J., Freear, A., Hartley, J., & Simmonds‐Buckley, M. (2019) . Delivering cognitive analytic consultancy to community mental health teams: Initial practice‐based evidence from a multi‐site evaluation.  Psychology and Psychotherapy: Theory Research and Practice. Early View 28 March 2019 (Open Access)

Spence C, Kellett S, Totterdell P, Parry G. (2019) Can cognitive analytic therapy treat hoarding disorder? An adjudicated hermeneutic single‐case efficacy design evaluation. Clin Psychol Psychother. 2019; 1–11.

Taylor, P. J., Perry, A., Hutton, P., Tan, R., Fisher, N., Focone, C., Griffiths, D., & Seddon, C. (2019). Cognitive Analytic Therapy for psychosis: A case series. Psychology and Psychotherapy, 92(3), 359–378.

Tyrer, R., & Masterson, C. (2019). Clients’ experience of change: An exploration of the influence of reformulation tools in cognitive analytic therapy. Clinical Psychology & Psychotherapy, 26(2), 167–174.


Curling L. , Kellett, S., Totterdell, P., Parry, G., Hardy, G., & Berry, K. (2018). Treatment of obsessive morbid jealousy with cognitive analytic therapy: An adjudicated hermeneutic single-case efficacy design evaluation. Psychology and Psychotherapy; Theory, Research and Practice, 91, 95-116.

Kellett, S., Hall, J., & Compton-Dickinson, S. (2018). Group cognitive analytic music therapy: a quasi-experimental feasibility study conducted in a high secure hospital. Nordic Journal of Music Therapy, doi: 10.1080/08098131.2018.1529697

Kellett, S. Stockton, C., Marshall, H., Hall, J. Jennings, C., & Degadillo, J. (2018). Efficacy of narrative reformulation during cognitive analytic therapy for depression: randomized dismantling trial. Journal of Affective Disorders, 239, 37-47.

Ryle A. & Kellett, S. (2018). Cognitive Analytic Therapy. Chapter 27 in W.J. Livesley. Handbook of Personality Disorders: Theory, Research and Treatment. NY: Guilford Press. 

Taplin, K., Greenhill, B., Seddon, C., & McGuire, J. (2018). Service User experiences of CAT Diagrams: and Interpretative Phenomenological Analysis. International Journal of Cognitive Analytic Therapy and Relational Mental Health, 2, 75–96.


Evans, M., Kellett, S., Heywood, S., Hall, J., & Majid, S. (2017). Cognitive analytic therapy for bipolar disorder: A pilot randomized controlled trial. Clinical Psychology and Psychotherapy, 24, 22-35.

Sandhu SK, Kellett S & Hardy G (2017) The development of a change model of “exits” during cognitive analytic therapy for the treatment of depression. Clinical Psychology and Psychotherapy 0, pp 1 – 11

Taylor, P.J., Jones, S., Huntley, C.D. and Seddon, C. (2017), What are the key elements of cognitive analytic therapy for psychosis? A Delphi study. Psychol Psychother Theory Res Pract, 90: 511-529.

Tully, R. J., & Barrow, A. (2017). Using an integrative, Cognitive Analytic Therapy (CAT) approach to treat intimate partner violence risk. Journal of Aggression, Conflict and Peace Research, 9(2), 128–140.


Berrios, R., Kellett, S., Fiorani, C., & Poggioli, M. (2016). Assessment of identity disturbance: Factor Structure and validation of the Personality Structure Questionnaire (PSQ) in an Italian sample. Psychological Assessment, 28, 27-35

Kellett S, Simmonds-Buckley M & Totterdell P (2016) Testing the Effectiveness of Cognitive Analytic Therapy for Hypersexuality Disorder: An Intensive Time-Series Evaluation. Journal of Sex & Marital Therapy pp 501 – 516

Sacks, M., Jagielska-Hall, D., & Jeffery S., (2016) Cognitive analytic therapy for high-risk sexual behaviour, Sexual and Relationship Therapy, 31:1, 20-31, DOI: 10.1080/14681994.2015.1114600


Calvert, R., Kellett, S., & Hagan, T. (2015). Group cognitive analytic therapy for female survivors of childhood sexual abuse. British Journal of Clinical Psychology, 54, 391-413

Kirkland, J., & Baron, E., (2015) Using a cognitive analytic approach to formulate a complex sexual and violent offender to inform multi-agency working: developing a shared understanding, Journal of Sexual Aggression, 21:3, 394-405, DOI: 10.1080/13552600.2014.939596


Calvert, R & Kellett, S. (2014). Cognitive analytic therapy: A review of the outcome evidence base for treatment. Psychology and Psychotherapy; Theory, Research and Practice, 87, 253-77

Kellett, S. & Hardy, G. (2014). The treatment of Paranoid Personality Disorder with CAT: A mixed methods single case experimental design. Clinical Psychology and Psychotherapy, 21, 452-64

Kellett, S. Wilbram, M., Davis, C. & Hardy, G. (2014). Team consultancy using cognitive analytic therapy: a controlled study in assertive outreach. Journal of Psychiatric and Mental Health Nursing, 21, 687-97

Ryle, A. Kellett, S. Hepple, J. & Calvert, R. (2014). Cognitive analytic therapy at 30. Advances in Psychiatric Treatment, 20, 258 – 268

Information for you about Cognitive Analytic Therapy (CAT)