CY-BOCS-II Rating Scale Overview
The Children's Yale-Brown Obsessive-Compulsive Scale, Second Edition (CY-BOCS-II) is a 10-item clinician-rated instrument that quantifies OCD symptom severity in youth aged 5-18 years, with scores ranging from 0-40, and treatment recommendations based on severity thresholds: mild OCD (8-15) warrants cognitive-behavioral therapy, moderate OCD (16-23) requires CBT with consideration of medication, severe OCD (24-31) necessitates combined CBT and pharmacotherapy, and treatment-refractory OCD (≥28) indicates need for intensified or alternative therapeutic strategies. 1, 2
Scale Structure and Administration
The CY-BOCS-II contains 10 items total: 5 items assessing obsessions and 5 items assessing compulsions, with each item rated from 0 (no symptoms) to 4 (extreme symptoms). 1, 2
The scale was modified from the original CY-BOCS by removing one item and adding a new item (item 4), allowing clinicians to generate both original CY-BOCS and CY-BOCS-II scores in a single administration through back-coding. 1
The instrument quantifies severity across three key parameters: (a) time spent on obsessions/compulsions, (b) level of distress experienced, and (c) degree of functional interference in daily activities. 1, 2
The CY-BOCS-II demonstrates excellent psychometric properties with internal consistency (α = 0.75-0.88), inter-rater reliability (ICC = 0.86-0.92), and test-retest reliability (ICC = 0.95-0.98). 3
Scoring Interpretation
Severity Classification:
0-7 points = Subclinical symptoms (no significant OCD pathology) 1, 2
8-15 points = Mild OCD (noticeable symptoms with minimal functional impairment) 1, 2
16-23 points = Moderate OCD (clear symptoms with moderate functional impairment) 1, 2
24-31 points = Severe OCD (marked symptoms with substantial functional impairment) 1, 2
≥28 points = Treatment-refractory OCD threshold (indicates severe, resistant disease requiring intensified intervention) 1, 2
Critical Assessment Pitfalls
Extensive avoidance behaviors can artificially lower CY-BOCS-II scores because patients who avoid triggering situations spend less observable time on active obsessions/compulsions despite severe functional impairment, leading to underestimation of true severity. 1, 2
Failure to evaluate family accommodation (such as parental reassurance-giving or participation in rituals) will bias interference ratings downward and cause underestimation of symptom severity. 1, 2
Clinicians must apply professional judgment when using this content-independent scale to correctly categorize obsessive-compulsive symptoms and differentiate them from other intrusive-thought disorders (e.g., generalized anxiety, PTSD intrusions, autism-related repetitive behaviors). 1
Treatment Recommendations Based on Score
Mild OCD (8-15):
- Initiate cognitive-behavioral therapy with exposure and response prevention (ERP) as first-line treatment. 2
Moderate OCD (16-23):
- Begin CBT with ERP as primary intervention. 2
- Consider adding selective serotonin reuptake inhibitor (SSRI) pharmacotherapy if CBT alone produces insufficient response after 8-12 weeks. 4
Severe OCD (24-31):
- Implement combined treatment with both CBT/ERP and SSRI pharmacotherapy from the outset. 4
- For autism spectrum disorder patients with comorbid OCD, pharmacotherapy may target compulsive-like behaviors when CY-BOCS scores indicate moderate-to-severe symptoms. 4
Treatment-Refractory OCD (≥28):
- A score of ≥28 identifies severe, treatment-refractory OCD in youth aged 8-18 years, indicating the need for intensified or alternative therapeutic strategies. 1, 2
- Consider augmentation strategies, intensive outpatient or residential OCD programs, or alternative medication trials beyond first-line SSRIs. 1, 2
Treatment Response Monitoring
A clinically meaningful treatment response is defined as ≥35% reduction from baseline CY-BOCS-II scores. 1
The CY-BOCS-II is sensitive to change and can effectively track symptom reduction across various treatment modalities, including internet-based telepsychiatry interventions. 1
Serial administration allows objective monitoring of treatment efficacy and guides decisions about treatment intensification or modification. 3, 5