Predicting Treatment Response in Body Dysmorphic Disorder with Interpretable Machine Learning
Omar Costilla-Reyes, Morgan Talbot
TL;DR
This study demonstrates that in predicting treatment outcomes for Body Dysmorphic Disorder, interpretable machine learning models—especially linear ones—perform comparably to more complex algorithms and highlight treatment credibility as a key, modifiable predictor. Using forward feature selection across 100 imputed datasets and 5-fold cross-validation, credibility consistently emerged as the first feature across outcomes, with decision-tree analyses revealing practical thresholds on a 27-point credibility scale. These thresholds (around 16 and 22) offer actionable guidance for clinicians to tailor interventions and resource allocation, while simpler models maintain robust performance. The findings advocate for integrating credibility-enhancing strategies, including digital, technology-assisted interventions, into personalized treatment plans, though they acknowledge limits due to small samples and self-report data, calling for larger, multi-site studies to establish causal effects. $30 ext%$ reductions and $16$-point thresholds are used as representative benchmarks to illustrate the approach, highlighting the potential impact of harnessing patient beliefs to improve engagement and outcomes in BDD care.
Abstract
Body Dysmorphic Disorder (BDD) is a highly prevalent and frequently underdiagnosed condition characterized by persistent, intrusive preoccupations with perceived defects in physical appearance. In this extended analysis, we employ multiple machine learning approaches to predict treatment outcomes -- specifically treatment response and remission -- with an emphasis on interpretability to ensure clinical relevance and utility. Across the various models investigated, treatment credibility emerged as the most potent predictor, surpassing traditional markers such as baseline symptom severity or comorbid conditions. Notably, while simpler models (e.g., logistic regression and support vector machines) achieved competitive predictive performance, decision tree analyses provided unique insights by revealing clinically interpretable threshold values in credibility scores. These thresholds can serve as practical guideposts for clinicians when tailoring interventions or allocating treatment resources. We further contextualize our findings within the broader literature on BDD, addressing technology-based therapeutics, digital interventions, and the psychosocial determinants of treatment engagement. An extensive array of references situates our results within current research on BDD prevalence, suicidality risks, and digital innovation. Our work underscores the potential of integrating rigorous statistical methodologies with transparent machine learning models. By systematically identifying modifiable predictors -- such as treatment credibility -- we propose a pathway toward more targeted, personalized, and ultimately efficacious interventions for individuals with BDD.
