What this Trial Is About

Body Dysmorphic Disorder (BDD) is a severe psychiatric condition characterized by persistent and intrusive preoccupations with perceived flaws in physical appearance, which are typically unnoticeable or appear minor to others. BDD is associated with significant psychological distress, functional impairment, and reduced quality of life. Despite its prevalence and clinical severity, BDD remains frequently underdiagnosed and misdiagnosed. While Cognitive Behavioural Therapy (CBT) and Selective Serotonin Reuptake Inhibitors (SSRIs) are currently considered standard treatments, emerging evidence suggests that third-wave psychotherapies, such as Acceptance and Commitment Therapy (ACT) and Compassion-Focused Interventions, may offer additional benefits. This project aims to advance clinical care and scientific understanding of BDD by developing, implementing, and evaluating the preliminary efficacy of MIND-over-MIRROR-a novel group-based psychological intervention integrating ACT and compassion-based strategies for individuals exhibiting high levels of BDD symptomatology. The intervention consists of eight weekly sessions and one follow-up booster session, delivered in an online or hybrid format. A randomized feasibility study will be conducted to examine the intervention's acceptability, practicality, and preliminary clinical efficacy in adults aged 18 to 65 years. A multi-method assessment framework will be employed, with self-report measures collected at baseline, post-intervention, and 3-month follow-up. Additionally, participants from experimental and control groups will report on their weekly BDD symptomatology. Participants in the intervention group who consent will also undergo computerized behavioural tasks and functional neuroimaging using functional near-infrared spectroscopy (fNIRS) to explore neural and cognitive correlates of treatment outcomes. Improvements are expected in core clinical outcomes, including BDD symptom severity, and it is hypothesized that changes in targeted psychological processes (e.g., self-compassion) will mediate these effects. This study will contribute novel and clinically relevant data regarding the feasibility and potential effectiveness of contextual behavioural therapies for BDD, with implications for both research and practice.

When The Mirror Is Wrong