Efficacy of an internet-based, therapist-guided cognitive behavioral therapy intervention for adolescents and young adults with body dysmorphic disorder: a randomized controlled trial

Michaela Schmidt; Katrin Schoenenberg; Julia E Engelkamp; Thomas Staufenbiel; Alexandra Martin; David D Ebert; Andrea S Hartmann

doi:10.1186/s12888-025-06797-1

Efficacy of an internet-based, therapist-guided cognitive behavioral therapy intervention for adolescents and young adults with body dysmorphic disorder: a randomized controlled trial

BMC Psychiatry. 2025 Apr 14;25(1):374. doi: 10.1186/s12888-025-06797-1.

Authors

Michaela Schmidt¹, Katrin Schoenenberg², Julia E Engelkamp³, Thomas Staufenbiel⁴, Alexandra Martin⁵, David D Ebert⁶, Andrea S Hartmann⁷

Affiliations

¹ Institute of Psychology, Department of Clinical Psychology and Psychotherapy, Osnabrück University, Osnabrück, Germany.
² Institute of Psychology, Department of Clinical Psychology and Psychotherapy, Kiel University, Kiel, Germany.
³ Department of Psychology, Clinical Psychology and Psychotherapy of Childhood and Adolescence, Konstanz University, Universitätsstraße 10, Postbox 905, 78464, Konstanz, Germany.
⁴ Institute of Psychology, Department of Research Methods, Diagnostics and Evaluation, Osnabrück University, Osnabrück, Germany.
⁵ Department of Psychology, Clinical Psychology and Psychotherapy, University of Wuppertal, Wuppertal, Germany.
⁶ Department of Sport and Health Sciences, Psychology and Digital Mental Health Care, Technical University of Munich, Munich, Germany.
⁷ Department of Psychology, Clinical Psychology and Psychotherapy of Childhood and Adolescence, Konstanz University, Universitätsstraße 10, Postbox 905, 78464, Konstanz, Germany. andrea.hartmann@uni-konstanz.de.

Abstract

Background: Body dysmorphic disorder (BDD) is particularly prevalent yet highly understudied and undertreated in adolescence. This study evaluates the efficacy of an internet-based, therapist-guided cognitive behavioral therapy (CBT) for adolescents and young adults with BDD compared to supportive online therapy as an active control condition.

Methods: In a single-blind, randomized controlled trial, N = 45 adolescents (aged 15-21 years) of all genders from German-speaking countries were assigned to 12 sessions of internet-based CBT (iCBT) or 12 weeks of supportive online therapy. The primary outcome was change in expert-rated BDD symptom severity from pre- to post-intervention (Yale-Brown Obsessive-Compulsive Scale Modified for Body Dysmorphic Disorder, BDD-YBOCS). Secondary outcomes included the remission and responder rate, changes in delusionality of appearance beliefs (BABS), self-rated BDD symptom severity (FKS), BDD cognitions (FKDK), quality of life (KINDL-R), and depressive symptoms (PHQ-9) from pre to post and to a 4-week follow-up.

Results: iCBT was more efficient than supportive online therapy on the BDD-YBOCS (p =.002), with a large between-group effect size at post-intervention (Hedges' g (SE) = 0.93 (0.42)), and on all secondary measures (p <.05), except for depressive symptoms (p =.068). All secondary outcome measures also showed significant improvements from pre to post iCBT, with moderate to large effect sizes, and gains were stable until the 4-week follow-up period. iCBT participants showed higher remission (61.5%) and responder rates (66.7%), compared to controls (0% and 26.7%), but only the difference in remission reached significance.

Conclusion: The results indicate the efficacy of internet-based CBT in comparison to an active control condition, thus contributing to the limited intervention research in adolescent BDD and adding a much-needed treatment option.

Trial registration: The trial was pre-registered on 2020/06/08 at the German Clinical Trials Register, DRKS00022055.

Keywords: Adolescents; Body dysmorphic disorder; Cognitive behavioral therapy; Online therapy; Randomized controlled trial.

Publication types

Randomized Controlled Trial

MeSH terms

Adolescent
Body Dysmorphic Disorders* / psychology
Body Dysmorphic Disorders* / therapy
Cognitive Behavioral Therapy* / methods
Female
Humans
Internet
Internet-Based Intervention*
Male
Quality of Life
Single-Blind Method
Treatment Outcome
Young Adult