Cognitive-Behavioral Therapy for Obsessive-Compulsive Disorder: A Comprehensive Synthesis of the Evidence

Abstract Background: Obsessive-Compulsive Disorder (OCD) is a chronic and disabling psychiatric condition characterized by intrusive thoughts and repetitive behaviors. Cognitive-Behavioral Therapy (CBT), particularly Exposure and Response Prevention (ERP), is regarded as the gold-standard psychological treatment for OCD. However, variations in efficacy, treatment adherence, and methodological quality across studies warrant a comprehensive synthesis of the available evidence. Objective: To systematically review and synthesize current evidence on the efficacy, mechanisms, and clinical outcomes of Cognitive-Behavioral Therapy in the treatment of Obsessive-Compulsive Disorder. Methods: A systematic search was conducted in PubMed, Scopus, PsycINFO, and Web of Science databases from inception to March 2025. Eligible studies included randomized controlled trials, meta-analyses, and systematic reviews evaluating CBT interventions for adults with OCD. Data extraction and quality assessment were performed independently by two reviewers following PRISMA guidelines. Results: Thirty-eight studies met inclusion criteria. Across trials, CBT—particularly ERP-based protocols—consistently demonstrated significant symptom reduction compared with control and pharmacological-only conditions. Meta-analytic evidence indicates moderate-to-large effect sizes (Hedges’ g = 0.65–1.20). Combined treatment with selective serotonin reuptake inhibitors (SSRIs) showed enhanced efficacy in severe cases. Treatment adherence, therapist expertise, and comorbid depression were identified as key moderators of outcomes. Conclusion: CBT remains a highly effective and evidence-based intervention for OCD. Despite robust efficacy, heterogeneity in methodological design and patient characteristics underscores the need for standardized protocols and further exploration of individual predictors of treatment response.