Children’s Yale-Brown Obsessive Compulsive Scale (CY-BOCS)

Abstract

The Children’s Yale-Brown Obsessive Compulsive Scale (CY-BOCS) is widely recognized as the international gold-standard clinician-rated instrument designed to assess the presence and dimensional severity of obsessive-compulsive symptomatology in pediatric populations aged 6 to 18 years. Developed as an adaptation of the adult Yale-Brown Obsessive Compulsive Scale (Y-BOCS) by Lawrence Scahill, Mark A. Riddle, and colleagues at the Yale Child Study Center, the instrument operationalizes obsessive-compulsive disorder (OCD) according to structural criteria delineated in both DSM and ICD nosologies. The assessment protocol consists of two interrelated components: an exhaustive, clinician-guided Symptom Checklist that screens for historical and current manifestations across thematic obsessive and compulsive domains, followed by a core 10-item Severity Scale. The severity dimension quantifies five core parameters—time spent, functional interference, subjective distress, active resistance, and degree of control—evaluated independently across obsessive thoughts (Items 1–5) and compulsive behaviors (Items 6–10).

Each severity item is rated along an anchored 5-point ordinal metric ranging from 0 (none) to 4 (extreme), yielding an Obsessions subtotal (0–20), a Compulsions subtotal (0–20), and a composite Global Severity Score ranging from 0 to 40. Extensively validated across clinical, community, and cross-cultural cohorts, the CY-BOCS displays robust psychometric properties, including high internal consistency (Cronbach’s $\alpha$ routinely spanning .86 to .91), exemplary inter-rater reliability (intraclass correlation coefficients ranging from .84 to .98), and sensitive treatment responsiveness. It has served as the primary outcome metric in landmark pediatric clinical trials, such as the Pediatric OCD Treatment Study (POTS). This comprehensive review explores the instrument’s empirical architecture, developmental adaptations, psychometric parameters, latent factor configurations, and clinical administration paradigms.

Keywords

Children’s Yale-Brown Obsessive Compulsive Scale, CY-BOCS, pediatric obsessive-compulsive disorder, psychometrics, clinician-rated assessment, symptom severity, cognitive-behavioral therapy, POTS study, obsessions, compulsions, factor structure, reliability, validity

Authors

The primary development and formal validation of the Children’s Yale-Brown Obsessive Compulsive Scale was spearheaded by a multidisciplinary team of child psychiatrists, clinical psychologists, and pediatric psychometricians based primarily at the Yale Child Study Center (Yale University School of Medicine) in collaboration with the Johns Hopkins University School of Medicine and Brown University.

• Lawrence Scahill, MSN, PhD: Professor of Pediatrics and Child Psychiatry, Yale Child Study Center; subsequently Professor of Pediatrics at Emory University School of Medicine. Recognized globally for pioneering clinical trial methodology in pediatric neurodevelopmental and psychiatric conditions.
• Mark A. Riddle, MD: Professor of Psychiatry and Behavioral Sciences and Director of the Division of Child and Adolescent Psychiatry, Johns Hopkins University School of Medicine; formerly affiliated with the Yale Child Study Center.
• Wayne K. Goodman, MD: D.C. and Irene Wise Chair of Psychiatry at Baylor College of Medicine; original architect of the adult Yale-Brown Obsessive Compulsive Scale (Y-BOCS), whose foundational psychometric framework served as the substrate for the pediatric adaptation.
• James F. Leckman, MD, PhD: Neison Harris Professor of Child Psychiatry, Pediatrics, and Psychology at the Yale Child Study Center; renowned investigator in the phenotypic overlap of Tourette syndrome, tic disorders, and pediatric OCD.
• Domenic V. Cicchetti, PhD: Senior Research Scientist and Biostatistician at the Yale Child Study Center and Veterans Affairs Connecticut Healthcare System; instrumental in establishing rigorous intraclass correlation methodology and psychometric thresholds for the scale.
• Collaborating Investigators: Karen McSwiggan-Hardin, MS; Sharon I. Ort, RN, MPH; and Kelly King, MSW, whose empirical contributions facilitated the clinical standardization and iterative refinement of child-friendly inquiry stems.

Purpose

The fundamental purpose of the CY-BOCS is to provide an objective, reliable, and standardized clinician-administered measurement of obsessive-compulsive symptom presence and severity in children and adolescents. Diagnosing and tracking pediatric OCD presents profound clinical challenges distinct from adult psychopathology. Young patients frequently lack developmental metacognitive awareness, struggle to articulate the egodystonic nature of their intrusive thoughts, or actively conceal rituals due to profound shame, embarrassment, or fear of parental reprimand. Furthermore, pediatric OCD rarely exists in isolation; it frequently intersects with complex family dynamics characterized by pervasive family accommodation, where parents and siblings become unwitting participants in extensive washing, checking, or ordering rituals.

The CY-BOCS addresses these developmental complexities through a semi-structured interview format that systematically integrates child self-report and parent observation. Rather than conflating the breadth of symptoms with clinical impairment, the instrument explicitly decouples symptom phenotype from severity magnitude. Clinical experience and psychometric research demonstrate that an adolescent may engage in dozens of transient, non-interfering ritualistic behaviors, while another child may exhibit only a single, catastrophic washing compulsion that occupies eight hours daily and completely halts school attendance. By evaluating symptom typology via the initial Symptom Checklist and subsequently rating universal parameters of functional interference, time occupation, internal distress, active resistance, and volitional control on the 10-item Severity Scale, the CY-BOCS isolates true functional morbidity.

In clinical practice, the CY-BOCS provides an empirical baseline against which therapeutic progress can be quantitatively charted. It is routinely used to establish treatment entry eligibility, identify idiosyncratic target symptoms for exposure and response prevention (ERP) hierarchies, and titrate psychopharmacological interventions such as selective serotonin reuptake inhibitors (SSRIs). In clinical research, the CY-BOCS represents the primary endpoint metric mandated by regulatory bodies (e.g., the U.S. Food and Drug Administration and the European Medicines Agency) for pharmacological licensing trials and randomized controlled trials evaluating psychotherapeutic protocols, including the definitive Pediatric OCD Treatment Study (POTS I & II).

Psychological Construct

The CY-BOCS evaluates the core psychological constructs defining Obsessive-Compulsive Disorder within contemporary psychiatric diagnostic manuals (DSM-5-TR and ICD-11). The overarching construct is partitioned into two mutually dependent yet psychometrically distinct operational domains: Obsessions and Compulsions. Each domain is appraised through five invariant dimensions that quantify the severity of the clinical phenotype.

Obsessive Phenomenon

Obsessions are defined as recurrent, persistent, intrusive, and unwanted thoughts, urges, mental images, or visceral sensations that penetrate consciousness and evoke clinically significant anxiety, apprehension, or distress. Within pediatric cohorts, obsessions frequently manifest within specific thematic typologies:

• Contamination Obsessions: Intense dread of dirt, bodily fluids, household chemicals, environmental toxins, viral or bacterial pathogens, or somatic contamination, often linked to catastrophic anticipations of severe illness or mortality for oneself or loved ones.
• Aggressive and Harm Obsessions: Egocynical intrusive fears of perpetrating catastrophic harm against oneself or others (e.g., stabbing a family member, pushing a classmate down stairs), impulsive shouting of blasphemies or obscenities, or catastrophic guilt rooted in the belief that bad thoughts will magically materialize into real-world tragedy (thought-action fusion).
• Symmetry, Ordering, and “Just Right” Sensations: An intense perceptual or somatic urge demanding that physical objects, bodily movements, or cognitive representations be aligned, balanced, or repeated until an internal sensory threshold of completeness or rightness is reached.
• Somatic, Sexual, and Scrupulosity Obsessions: Hyperfocus on bodily functions, hyper-guilt surrounding moral, ethical, or religious transgressions, and developmentally intrusive sexual imagery that induces severe self-reproach.

Compulsive Phenomenon

Compulsions represent repetitive, stereotyped behavioral acts or covert mental rituals that an individual feels rigidly driven to perform, either in direct response to an active obsession or according to idiosyncratic, unbending rules. While compulsions are intended to neutralize perceived threat, discharge unbearable sensory distress, or prevent a catastrophic outcome, they are objectively non-contingent or grossly disproportionate to the actual danger. In pediatric patients, typical compulsive expressions include:

• Cleaning and Washing: Prolonged ritualized handwashing, sterilization of personal belongings, ritualized showering routines lasting multiple hours, and extensive avoidance of contaminated environmental objects.
• Checking Behaviors: Iterative verification that doors are locked, electrical appliances are switched off, homework contains zero errors, or that no individuals were harmed during daily transits.
• Repeating and Counting: Performing motor behaviors (stepping through thresholds, turning switches, sitting and standing) in fixed numerical multiples or re-reading and re-writing passages until perfection is achieved.
• Parental Reassurance Seeking and Involvement: Coercing caregivers to provide repetitive verbal confirmations (“Are you sure I am safe?”) or forcing family members to perform the child’s decontamination or symmetry routines.

The Five Dimensional Severity Parameters

The severity construct on the CY-BOCS is quantified across five universal dimensional indicators evaluated in parallel across both symptom spheres:

1. Time Occupied: The cumulative temporal burden incurred by obsessions or rituals throughout a typical 24-hour cycle.
2. Functional Interference: The degree to which intrusive thoughts or behavioral rituals impair educational achievement, peer socialization, autonomous activities of daily living, and family routines.
3. Subjective Distress: The quantitative level of emotional suffering, autonomic arousal, affective anguish, or somatic dysregulation induced by obsessions, or experienced when compulsions are blocked.
4. Active Resistance: The extent to which the youth attempts to divert, suppress, dispute, or physically halt the expression of the obsessive thought or compulsive routine.
5. Volitional Control: The capacity of the child to successfully terminate or arrest the intrusive cognitive intrusion or compulsive behavioral loop once initiated.

Theoretical Framework

The theoretical architecture underpinning the CY-BOCS is rooted in cognitive-behavioral models of psychopathology, behavioral learning theories, and contemporary developmental neurobiology.

Cognitive-Behavioral and Inhibitory Learning Models

From a cognitive-behavioral perspective (e.g., Salkovskis, Rachman), intrusive thoughts, impulses, and images are universal human phenomena. The etiology of OCD resides not in the initial presence of the intrusion, but in the catastrophic, dysfunctional appraisal assigned to that intrusion. In youth with OCD, intrusions are cognitively appraised as denoting imminent personal responsibility, profound moral corruption, or immediate objective danger. This catastrophic appraisal activates acute subjective distress and physiological hyperarousal. To rapidly downregulate this distressing state, the individual engages in compulsive rituals or safety-seeking behaviors.

According to classical Mowrerian two-factor theory and modern inhibitory learning paradigms, compulsive rituals operate via potent negative reinforcement mechanisms: because performing the ritual immediately dissipates the visceral panic, the behavioral compulsion is strongly reinforced. However, this neutralization prevents the natural extinction of conditioned distress, inhibits the acquisition of corrective disconfirmatory safety data, and perpetuates the cycle. The CY-BOCS operationalizes this model by systematically measuring the interplay between internal distress (the conditioned response) and compulsive rituals (the operant avoidance mechanism).

Neurodevelopmental and Corticostriatal Circuitry

From a neurobiological standpoint, pediatric OCD is conceptualized as a disorder of functional connectivity across the cortico-striatal-thalamo-cortical (CSTC) loops, which regulate behavioral selection, cognitive flexibility, conflict monitoring, and sensorimotor gating. Hyperactivity within the orbitofrontal cortex (OFC) and anterior cingulate cortex (ACC), paired with dysregulated inhibitory feedback within the caudate nucleus and basal ganglia, impairs the brain’s internal signaling that a task has reached safe completion. This failure of cognitive closure produces persistent feelings of incompleteness (“not-just-right” experiences), driving repetitive motor routines. The CY-BOCS evaluates these neurocircuit impairments by directly querying the youth’s loss of volitional control and inability to suppress compulsive behavioral outputs.

Developmental Psychopathology and Systemic Accommodation

Unlike adult scales, the theoretical framework of the CY-BOCS incorporates developmental psychology principles. It recognizes that children possess variable cognitive maturation, imperfect linguistic grasp of internal mental states, and marked fluctuations in insight. Young children may not perceive their compulsions as unreasonable or excessive (egodystonic), but may instead perceive them as vital self-protection (egosyntonic). Furthermore, pediatric psychopathology exists within a familial matrix. Theoretical formulations of pediatric OCD emphasize family accommodation—the process whereby caregivers alter their own behaviors, provide constant verbal reassurance, or assist in rituals to reduce the child’s acute distress. The CY-BOCS framework acknowledges this systemic interdependence by formally integrating parent-reported behavioral observations into the clinician’s ultimate diagnostic scoring synthesis.

Validity

The Children’s Yale-Brown Obsessive Compulsive Scale has undergone extensive psychometric evaluation, demonstrating exceptional construct, convergent, discriminant, and predictive validity across diverse clinical samples and international translations.

Convergent Validity

Convergent validity has been established through strong, statistically significant correlations with other standardized measures of pediatric OCD symptomatology and clinical impairment. In the seminal psychometric validation study by Scahill et al. (1997), the CY-BOCS Total Score demonstrated robust positive correlations with the National Institute of Mental Health Global Obsessive Compulsive Scale (NIMH-GOCS; $r = .67, p < .001$) and the Clinical Global Impressions – Severity Scale (CGI-S; $r = .58, p < .001$). Subsequent investigations by Storch et al. (2004) confirmed high convergent validity with the Obsessive Compulsive Scale of the Child Behavior Checklist (CBCL-OCS; $r = .52, p < .001$) and the Multidimensional Anxiety Scale for Children (MASC) OCD subscale ($r = .49, p < .001$).

Discriminant Validity

Discriminant validity is supported by the instrument’s capacity to distinguish obsessive-compulsive severity from generalized pediatric affective distress, externalizing disruptive behaviors, and unrelated psychological phenotypes. Studies evaluating clinical cohorts have documented significantly lower correlations between CY-BOCS Total Scores and standardized depression measures, such as the Children’s Depression Inventory (CDI; $r = .28$ to $.35$), and measures of externalizing psychopathology, such as the CBCL Rule-Breaking and Aggressive Behavior scales ($r = .12$ to $.21$). While anxiety and depressive symptoms are common secondary sequelae of OCD, the modest magnitude of these correlations confirms that the CY-BOCS measures unique variance attributable specifically to OCD rather than diffuse internalizing or negative affectivity.

Predictive and Treatment Sensitivity

The scale displays remarkable sensitivity to treatment-induced clinical change, which has made it the primary outcome measure in major pediatric psychopharmacological and psychotherapy clinical trials. In the landmark Pediatric OCD Treatment Study (POTS, 2004), the CY-BOCS successfully differentiated the treatment efficacy of cognitive-behavior therapy alone, sertraline alone, and combined CBT plus sertraline against placebo over 12 weeks. Psychometric analyses demonstrate that a 25% to 35% reduction in baseline CY-BOCS Total Score reliably predicts clinical response, while a post-treatment score of $le 12$ denotes excellent clinical remission, confirming its predictive and evaluative utility.

Reliability

The CY-BOCS exhibits outstanding reliability parameters across multiple testing modalities, including internal consistency, inter-rater concordance, and test-retest stability.

Internal Consistency

Multiple investigations have demonstrated high internal consistency across the total scale and its primary subscales. In the foundational validation study by Scahill et al. (1997) encompassing children and adolescents aged 8 to 17 years, Cronbach’s alpha ($lpha$) for the CY-BOCS Total Score was reported at .87. The Obsessions subscale yielded an alpha of .80, while the Compulsions subscale produced an alpha of .82. Replications across diverse samples have consistently corroborated these parameters:

• Storch et al. (2004): Documented a Cronbach’s alpha of .90 for the Total Score, .86 for the Obsessions dimension, and .84 for the Compulsions dimension in an outpatient clinical cohort.
• Freeman et al. (2003): Validating a developmentally adapted version for young children aged 5 to 8 years, established a Total Score internal consistency of $lpha = .86$.
• Cross-Cultural Adaptations: International validation studies across Dutch, Swedish, Spanish, Japanese, and Brazilian Portuguese translations report composite internal consistency coefficients consistently spanning $lpha = .85$ to $.92$.

Inter-Rater Reliability

Given that the CY-BOCS relies upon clinician elicitation, interpretation, and synthesis of multi-informant data, inter-rater reliability is paramount. Scahill et al. (1997) evaluated inter-rater agreement utilizing independent clinician ratings across live and videotaped interviews. The intraclass correlation coefficient (ICC) for the Total Score reached an exceptional .91, with the Obsessions subscale achieving an ICC of .91 and the Compulsions subscale yielding an ICC of .87. Independent replications (e.g., Storch et al., 2005) have documented inter-rater ICCs ranging between .94 and .98 among trained evaluators, demonstrating that standardized anchor definitions minimize clinician-dependent scoring variance.

Test-Retest Stability

In the absence of active psychotherapeutic or pharmacological intervention, the CY-BOCS demonstrates solid test-retest reliability across short-term intervals (e.g., 2 to 6 weeks). Scahill and colleagues reported a test-retest Pearson correlation of $r = .79$ ($p < .001$) over a 2- to 3-week test interval. This indicates that while the tool remains highly sensitive to therapeutic modifications, spontaneous fluctuations among untreated, clinically stable youths remain minimal.

Factor Analysis

The latent factor structure of the CY-BOCS has been a subject of extensive psychometric investigation using both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). While the scale was conceptually constructed around two correlated a priori structural domains—Obsessions (Items 1–5) and Compulsions (Items 6–10)—empirical factor analyses have uncovered more nuanced latent dynamics.

Two-Factor Structural Models

Initial factor analytic investigations conducted by Scahill et al. (1997) largely confirmed the two-dimensional conceptualization, with items assessing obsessive severity loading distinctly on Factor 1 and items capturing compulsive severity loading on Factor 2. However, multiple subsequent CFA investigations (e.g., McKay et al., 2003; Storch et al., 2005) demonstrated that alternative two-factor configurations provide superior empirical fit to the data.

Rather than partitioning along the symptom content axis (Obsessions vs. Compulsions), empirical data frequently cluster into an Obsession-Compulsion Severity / Disturbance factor and a Resistance / Control factor:

• Factor 1 (Disturbance / Severity): Consists of Items 1, 2, 3 (Obsessions: Time, Interference, Distress) and Items 6, 7, 8 (Compulsions: Time, Interference, Distress). These items exhibit exceptionally high inter-item correlations and factor loadings exceeding .70.
• Factor 2 (Resistance and Control): Consists of Items 4, 5 (Obsessions: Resistance, Control) and Items 9, 10 (Compulsions: Resistance, Control). These items capture the youth’s active regulatory mechanisms and behavioral agency.

Item Functioning: The Resistance Paradox

A consistent empirical finding in structural analyses of the CY-BOCS involves the psychometric performance of the Resistance items (Item 4 and Item 9). In multiple confirmatory models, these items display weak or non-significant factor loadings on the primary severity dimension. Clinicians and psychometricians have termed this the “resistance paradox.”

In pediatric psychopathology, a child with mild OCD may exhibit active, vigorous resistance against intrusive rituals, resulting in a low severity score on that item. Conversely, a child with profoundly severe, chronic, or debilitating OCD may have completely exhausted their psychological resources, yielding zero resistance. This lack of active fighting may counterintuitively be scored as low resistance on some rubrics, or conversely reflect total surrender to the disorder. Consequently, modern structural equation models often show superior fit indices when Resistance items are omitted, or modeled as an independent coping construct rather than a direct linear marker of disorder severity.

Structural Equation Model Fit Indices

CFA studies evaluating refined factor structures (such as a hierarchical two-factor model or a bifactor model featuring a robust general “OCD Severity” factor alongside specific residual factors) have reported strong model fit indices across large pediatric cohorts ($N > 400$):

• Comparative Fit Index (CFI) $ge .95$
• Tucker-Lewis Index (TLI) $ge .94$
• Root Mean Square Error of Approximation (RMSEA) $le .06$ (90% CI: .04 to .08)
• Standardized Root Mean Square Residual (SRMR) $le .05$

Instrument / Measurement Tool

The CY-BOCS is a semi-structured clinician-rated interview designed for children and adolescents ages 6 to 18. Its clinical administration involves a multi-informant approach that synthesizes clinical judgment with reports from both the child and their caregivers.

Structural Architecture

• Component 1: The Symptom Checklist: A comprehensive inventory spanning over 70 specific manifestations of obsessive-compulsive phenomena grouped into thematic categories (e.g., Contamination, Aggressive, Sexual, Hoarding, Religious/Moral, Somatic, Symmetry/Arranging, Checking, Washing, Repeating, Counting, Ordering, and Miscellaneous rituals). The checklist documents both historical lifetime occurrences and current symptoms present during the past week. From this list, the clinician identifies and documents the patient’s primary, clinically dominant target symptoms.
• Component 2: The Core Severity Scale: A standardized 10-item clinician-rated metric that evaluates the target symptoms identified during the checklist phase across a defined temporal window (standardly the preceding 7 days).

Administration Methodology

• Respondent Paradigm: Joint administration involving the child and primary caregivers. Best clinical practice recommends interviewing the child and parents together, or conducting brief independent interviews followed by a joint reconciliation discussion.
• Clinician Role: The clinician does not simply accept subjective numeric ratings. Instead, the clinician uses standardized exploratory prompts, evaluates corroborating real-world behavioral examples, cross-examines discrepancies between child self-report and parent observation, and assigns the definitive numeric score based on standardized operational anchor criteria.
• Administration Duration: Approximately 45 to 65 minutes for the initial diagnostic baseline assessment (including the complete Symptom Checklist); 15 to 25 minutes for serial treatment monitoring evaluations (administering only the 10-item Severity Scale focused on tracked target symptoms).

Scoring Rubric and Quantitative Metrics

• Item Rating Scale: Each of the 10 items is scored on an anchored 5-point ordinal continuum from 0 to 4:
  • 0: None (No symptoms / complete control / unhindered resistance)
  • 1: Mild (Slight time occupation / minimal interference / manageable distress)
  • 2: Moderate (Definite, distinct intrusion / clear functional interference / manageable but marked distress)
  • 3: Severe (Substantial time occupation / extensive impairment / marked internal anguish)
  • 4: Extreme (Near-constant occupation / completely disabling / incapacitating distress)
• Subscale Computations:
  • Obsessions Subtotal Score: Sum of Items 1 through 5 (Score Range: 0 to 20).
  • Compulsions Subtotal Score: Sum of Items 6 through 10 (Score Range: 0 to 20).
  • Total CY-BOCS Severity Score: Sum of all 10 items (Score Range: 0 to 40).

Established Severity Cutoffs

• 0 – 7: Subclinical or Remitted (typical target for post-treatment therapeutic success)
• 8 – 15: Mild OCD symptomatology
• 16 – 23: Moderate OCD (standard inclusion criterion threshold for clinical trials)
• 24 – 31: Severe, functionally debilitating OCD
• 32 – 40: Extreme, profoundly incapacitating, and catastrophic presentation

Permissions & Fee and Test Year

The Children’s Yale-Brown Obsessive Compulsive Scale was first formally standardized and published in its definitive psychometric validation form in 1997 by Lawrence Scahill and colleagues. The scale was developed under federal academic research grants funded by the National Institute of Mental Health (NIMH).

In accordance with its academic origins and public health mission, the traditional paper-and-pencil version of the CY-BOCS is considered in the public domain for non-commercial clinical, educational, and empirical academic research purposes. Clinicians and researchers are permitted to reproduce and administer the scale without paying licensing fees or royalties to the original authors or academic institutions. However, users are strictly required to preserve the original item text, scoring anchors, and psychometric structure without unauthorized alterations. For commercial applications, electronic medical record (EHR) software integrations, or industry-sponsored multi-site pharmaceutical registration trials, formal administrative licensing or proprietary permissions may be required through the copyright holders or academic technology transfer offices associated with the Yale Child Study Center.

References

Below are primary academic references documenting the development, psychometric properties, factor structure, and clinical applications of the CY-BOCS:

• Freeman, J. B., Flessner, C. A., Garcia, A. M., & Leonard, H. L. (2011). The Children’s Yale-Brown Obsessive Compulsive Scale: Psychometric properties in a developmental sample. Journal of Clinical Child & Adolescent Psychology, 40(2), 246–254. https://doi.org/10.1080/15374416.2011.546045
• Goodman, W. K., Price, L. H., Rasmussen, S. A., Mazure, C., Fleischmann, R. L., Hill, C. L., Heninger, G. R., & Charney, D. S. (1989). The Yale-Brown Obsessive Compulsive Scale. I. Development, use, and reliability. Archives of General Psychiatry, 46(11), 1006–1011. https://doi.org/10.1001/archpsyc.1989.01810110048007
• McKay, D., Neziroglu, F., Stevens, J., & Yaryura-Tobias, J. A. (2003). Factor structure of the Children’s Yale-Brown Obsessive-Compulsive Scale: Evidence for a two-factor solution. Journal of Anxiety Disorders, 17(5), 517–527. https://doi.org/10.1016/S0887-6185(02)00242-1
• Pediatric OCD Treatment Study (POTS) Team. (2004). Cognitive-behavior therapy, sertraline, and their combination for children and adolescents with obsessive-compulsive disorder: The Pediatric OCD Treatment Study (POTS) randomized controlled trial. JAMA, 292(16), 1969–1976. https://doi.org/10.1001/jama.292.16.1969
• Scahill, L., Riddle, M. A., McSwiggan-Hardin, K., Ort, S. I., King, R. A., Goodman, W. K., Cicchetti, D. V., & Leckman, J. F. (1997). Children’s Yale-Brown Obsessive Compulsive Scale: Reliability and validity. Journal of the American Academy of Child & Adolescent Psychiatry, 36(6), 844–852. https://doi.org/10.1097/00004583-199706000-00023
• Storch, E. A., Murphy, T. K., Geffken, G. R., Soto, O., Sajid, M., Allen, P., Roberti, J. W., Killiany, E. M., & Goodman, W. K. (2004). Psychometric evaluation of the Children’s Yale-Brown Obsessive-Compulsive Scale. Psychiatry Research, 129(1), 91–98. https://doi.org/10.1016/j.psychres.2004.06.009
• Storch, E. A., Shapira, N. A., Dimastrogiovanni, D., Geffken, G. R., Murphy, T. K., & Goodman, W. K. (2005). The factor structure of the Children’s Yale-Brown Obsessive-Compulsive Scale: Evidence for a two-factor model. Depression and Anxiety, 22(4), 199–205. https://doi.org/10.1002/da.20120

Items of the Scale