Assessment of disruptive Symptoms (ASD-IV-P)

Abstract

The Assessment of disruptive Symptoms-DSM-IV Version – For Parents (ASD-IV-P) is an evidence-based clinical and research psychometric instrument designed to evaluate the continuum of externalizing behavioral pathology in children and adolescents, specifically targeting Attention-Deficit/Hyperactivity Disorder (ADHD)—both Inattentive and Hyperactive-Impulsive presentations—and Oppositional Defiant Disorder (ODD), alongside context-dependent functional impairment and developmental onset. Developed by Daniel A. Waschbusch, Shannon J. Sparkes, and the Northern Partners in Action for Child and Youth Services (2003), the instrument was formulated to address a foundational limitation inherent in traditional psychiatric symptom rating scales: the severe positive skewness and truncate floor effects that emerge when absolute frequency anchors (e.g., “Never,” “Often”) are applied to general population and community cohorts. Comprising 38 structured items—including 26 core symptom indicators mapped directly to the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), 9 domain-specific functional impairment ratings, and 3 age-of-onset queries—the ASD-IV-P employs a unique relative peer-comparison response format ranging from 0 (“Much less than others”) to 4 (“Much more than others”). This structural framework establishes an approximately normal distribution of behavioral traits, capturing not only elevated clinical deviance but also exceptionally low levels of disruptive behavior. Psychometric evaluations demonstrate robust internal consistency (Cronbach’s alphas typically exceeding .88 to .94 across subscales), exceptional convergent validity with standard rating systems, and a replicated three-factor latent structure (Inattention, Hyperactivity-Impulsivity, and Oppositional Defiance). This article provides a comprehensive academic analysis of the ASD-IV-P, examining its theoretical architecture, psychometric validity, dimensional measurement mechanics, and clinical utility.

Keywords

Assessment of disruptive Symptoms, ASD-IV-P, Attention-Deficit/Hyperactivity Disorder, Oppositional Defiant Disorder, Conduct Disorder, externalizing psychopathology, peer-comparison rating scale, functional impairment, psychometrics, normal distribution, behavioral rating scales

Authors

The Assessment of disruptive Symptoms-DSM-IV Version – For Parents was developed through a scientific collaboration between academic pediatric psychopathology researchers and community mental health organizations:

• Daniel A. Waschbusch, Ph.D. — Professor of Psychiatry and Behavioral Health and Vice Chair for Research at Penn State Health Milton S. Hershey Medical Center / Penn State College of Medicine. At the time of scale development, Dr. Waschbusch was affiliated with the Department of Psychology at Dalhousie University, Halifax, Nova Scotia, Canada. His extensive research focuses on the developmental psychopathology of ADHD, ODD, Conduct Disorder, and callous-unemotional (CU) traits in children.
• Shannon J. Sparkes, M.A. — Clinical researcher and psychologist affiliated with Dalhousie University and regional child development initiatives in Nova Scotia, Canada, specializing in pediatric behavioral assessment and statistical modeling.
• Northern Region Partners In Action for Children and Youth — A collaborative consortium of mental health clinicians, educators, pediatric social workers, and child welfare advocates in Nova Scotia, Canada, dedicated to optimizing evidence-based pediatric assessment, prevention protocols, and clinical outcomes.

Purpose

The primary clinical and empirical purpose of the ASD-IV-P is to quantify the severity, pervasiveness, and functional impairment of disruptive behavior disorders across a fully continuous, normally distributed spectrum. Standard clinical diagnostic taxonomies, such as the DSM-IV and its successor the DSM-5, are inherently categorical, conceptualizing psychiatric illness in terms of diagnostic thresholds determined by arbitrary symptom counts. When translated into conventional parent rating scales—such as the SNAP-IV, the Child Behavior Checklist (CBCL), or the Vanderbilt ADHD Diagnostic Parent Rating Scale—items typically utilize absolute frequency or absolute severity response scales (e.g., “0 = Not at all, 1 = Just a little, 2 = Pretty much, 3 = Very much”). While these formats are functional within acute psychiatric clinics, they generate marked psychometric limitations in epidemiological, school-based, and non-referred community samples.

Specifically, in general population distributions, the vast majority of non-clinical children receive ratings of 0 (“Not at all”) on most disruptive behavior items. This produces extreme positive skewness, significant non-normality, and severe floor effects (statistical truncation at the lower boundary of the measurement space). These distributional anomalies violate the fundamental assumptions of standard parametric inferential statistics, including ordinary least squares (OLS) regression, structural equation modeling (SEM), and analysis of variance (ANOVA). Consequently, variance among children exhibiting normative versus exceptionally well-regulated behavior is completely obscured. Researchers and clinicians are unable to distinguish between an average child and an exceptionally compliant, hyper-focused, or behaviorally inhibited child, potentially missing protective factors and subtle developmental trajectories.

The ASD-IV-P directly addresses this psychometric challenge by altering the reference framing of the response anchors. Rather than assessing absolute behavioral frequency, parents are instructed to rate their child’s behaviors relative to same-age and same-sex peers (“In the past six months, as compared to other children of the same age and sex, your child…”) on a five-point scale from “Much less than others” (0) to “Much more than others” (4), centered on “Same as others” (2). This comparative calibration accomplishes several critical objectives:

• Distributional Normalization: It produces an approximately bell-shaped, normal distribution across the entire continuum of externalizing symptoms, eliminating floor effects and preserving linear variance across the lower, middle, and upper quartiles.
• Detection of Hypo-Disruptive and Adaptive Functioning: The scale demarcates individuals with unusually low levels of disruptive characteristics (scores of 0 or 1), enabling research into social competence, hyper-compliance, over-regulation, and resiliency mechanisms.
• Dual-Component Diagnostic Mapping: Beyond symptom frequency, the ASD-IV-P explicitly operationalizes DSM criterion requirements by embedding dedicated sub-modules that quantify functional impairment across multiple ecological settings (Home, School, Other) and document the chronological age of onset.
• Enhanced Statistical Sensitivity: By stabilizing variance and restoring normality, the tool optimizes statistical power in longitudinal studies, gene-environment interaction analyses, and clinical trial outcomes where fine-grained dimensional change is monitored.

Psychological Construct

The ASD-IV-P operationalizes externalizing child psychopathology as a multi-dimensional construct comprising three primary behavioral symptom domains and one cross-situational functional impairment domain. Each symptom domain aligns with the diagnostic architecture established in clinical nosology:

1. Hyperactivity and Impulsivity (Items 1–9)

Hyperactivity and impulsivity represent deficits in behavioral inhibition, motor regulation, and delay of gratification. In the ASD-IV-P, this dimension evaluates gross motor overactivity, verbal disinhibition, and impatience. Rather than simply evaluating whether a child moves excessively, the construct assesses whether the child’s kinetic output and regulatory failures deviate from normative developmental expectations. Specific behavioral indicators include:

• Verbal Disinhibition: Interrupting conversations, intruding on others’ games (Item 1), talking excessively without regard to social context (Item 2), and blurting out answers before inquiries are fully stated (Item 4).
• Motoric Restlessness: Micro-movements such as fidgeting with hands or squirming in seats (Item 3), inability to remain seated in structured settings (Item 6), and sustained feelings of being driven by a motor (Item 8).
• Impaired Self-Regulation: Inability to engage in leisure activities quietly (Item 5), difficulty awaiting one’s turn in social or academic situations (Item 7), and inappropriate running or climbing when contextual norms demand stillness (Item 9).

2. Inattention (Items 14–22)

The inattention construct reflects core neurocognitive impairments in sustained attention, selective attention, working memory, and executive organization. It is not characterized by open defiance, but rather by an inability to mobilize and maintain cognitive effort toward non-intrinsically rewarding tasks. The behavioral manifestations captured include:

• Attentional Selectivity and Distractibility: Susceptibility to extraneous stimuli and failure to attend to environmental details, resulting in careless errors on academic coursework (Items 14, 16).
• Auditory and Receptive Engagement: The outward appearance of not listening or registering verbal input when spoken to directly (Item 15), alongside pervasive difficulties holding attention during prolonged tasks or recreational activities (Item 18).
• Executive Execution and Task Management: Systemic failure to follow instructions to completion (independent of oppositional motivation; Item 17), chronic aversion to tasks requiring sustained cognitive stamina (Item 20), systemic deficits in organizing activities and materials (Item 21), losing critical everyday instruments (Item 19), and pervasive forgetfulness during regular daily routines (Item 22).

3. Oppositional Defiance (Items 27–34)

The construct of Oppositional Defiant Disorder encompasses an enduring pattern of angry/irritable mood, argumentative/defiant behavior, and vindictiveness toward authority figures and peers. It is conceptually distinct from ADHD, capturing emotional dysregulation and interpersonal hostility rather than neurodevelopmental regulatory failure. Within the ASD-IV-P, ODD is measured via:

• Argumentative and Defiant Behaviors: Active resistance to or refusal to comply with adult directives and established rules (Item 30), arguing with figures of authority (Item 27), and shifting accountability by blaming others for personal mistakes or misbehavior (Item 29).
• Angry, Irritable Mood and Affective Lability: Frequent temper outbursts (Item 33), touchy or easily annoyed temperament (Item 32), and chronic feelings of anger, resentment, and bitterness (Item 31).
• Vindictiveness and Interpersonal Malice: Deliberately irritating or provoking others (Item 34) and engaging in spiteful or vindictive retaliatory actions (Item 28).

4. Cross-Situational Impairment and Chronological Onset (Items 10–13, 23–26, 35–38)

A central tenet of clinical psychometrics is that elevated behavioral topography does not automatically equate to pathology; diagnostic validity mandates verifiable functional impairment. The ASD-IV-P explicitly conceptualizes impairment across three major life domains: Home (family relationships, compliance with domestic routines), School (academic performance, classroom decorum), and Other Settings (peer socialization, organized athletics, community activities). Each behavioral dimension has dedicated impairment scales (rated 0–4) and an open-ended index documenting the child’s chronological age at symptom manifestation, satisfying the developmental and cross-situational verification standards of clinical practice.

Theoretical Framework

The conceptual underpinning of the ASD-IV-P rests at the intersection of three major psychological frameworks: Dimensional Psychopathology and the Hierarchical Taxonomy of Psychopathology (HiTOP), Social Comparison Theory, and Classical Test Theory (CTT) vs. Item Response Theory (IRT) distributional mechanics.

Dimensional Psychopathology and HiTOP

Historically, psychiatric diagnostic classification has adhered to the medical model, assuming that clinical syndromes represent discrete, qualitative taxons that are qualitatively distinct from normal psychological variation. However, extensive developmental psychopathology research (e.g., Achenbach, 1991; Hudziak et al., 2007) demonstrates that externalizing disorders like ADHD and ODD are quantitative extremes of continuous behavioral traits that are distributed continuously throughout the human population. The HiTOP model frames these conditions as nested components within a broad Externalizing Spectrum, consisting of an Inattention-Hyperactivity subfactor and an Antagonistic/Conduct subfactor.

The ASD-IV-P was theoretically engineered to align with this continuous paradigm. By avoiding artificial bifurcations (“disordered” vs. “non-disordered”), the scale operationalizes psychopathology as a continuous latent trait ($\theta$). It assumes that every child possesses a specific location along this trait continuum, where low scores indicate strong behavioral self-regulation or docility, median scores reflect normative developmental disruption, and high scores indicate clinical pathology requiring targeted intervention.

Social Comparison Theory

The incorporation of peer-comparison anchors directly applies Leon Festinger’s Social Comparison Theory (1954) to informant-based rating methodology. When parents complete traditional scales with subjective absolute anchors (e.g., “Does this child fidget ‘often’?”), they face an ambiguous cognitive task. One parent might interpret “often” as twice an hour, whereas another might interpret it as twice a week. This introduces substantial idiosyncratic rater variance and measurement error.

The ASD-IV-P anchors parent perceptions to an explicit, ecologically grounded normative standard: “other children of the same age and sex.” By calibrating their evaluations against this normative mental baseline, parents subconsciously control for expected developmental phases (e.g., the high activity level typical of 4-year-old boys) and gender-specific baseline variations. This reframing minimizes rater contrast effects and generates variance centered precisely on a neutral developmental benchmark (“Same as others”).

Distributional Normalization and Statistical Power

From a classical psychometric standpoint, absolute rating scales of rare maladaptive behaviors inevitably suffer from severe positive skewness. Waschbusch and Sparkes (2003) demonstrated that statistical models applied to severely skewed data yield attenuated correlation coefficients, deflated effect sizes, and distorted factor structures. By introducing a symmetric 5-point comparative scale, the ASD-IV-P restores a Gaussian distribution. This distribution fulfills the mathematical assumptions required for advanced multivariate modeling, longitudinal growth curve modeling, and quantitative behavioral genetics, ensuring that findings reflect true behavioral variance rather than statistical artifacts caused by floor effects.

Validity

The construct, convergent, discriminant, and criterion validity of the ASD-IV-P has been confirmed through empirical research examining child and adolescent clinical cohorts and community school populations.

Construct and Structural Validity

Construct validity is evidenced by the tool’s capacity to operationalize DSM diagnostic criteria while yielding continuous, normally distributed scores. In the foundational validation investigation conducted by Waschbusch, Sparkes, and the Northern Region Partners in Action (2003), the scale was administered to parent cohorts alongside conventional disruptive behavior scales. Goodness-of-fit evaluations revealed that the peer-comparison format achieved distributional parameters approaching normality (skewness and kurtosis coefficients generally falling between -1.0 and +1.0), whereas traditional scales administered to the same samples displayed severe positive skewness (skewness values frequently exceeding +2.5 to +3.5).

Convergent Validity

Convergent validity has been established through strong, statistically significant correlations with widely validated child psychopathology rating scales:

• SNAP-IV Rating Scale: ASD-IV-P subscale scores exhibit robust correlations with corresponding SNAP-IV dimensions. The Inattention subscale correlates strongly with SNAP-IV Inattention ($r = .82$ to $.89$), and the Hyperactivity-Impulsivity subscale correlates with SNAP-IV Hyperactivity-Impulsivity ($r = .79$ to $.86$).
• Child Behavior Checklist (CBCL): The ASD-IV-P subscales show high convergent validity with the CBCL Attention Problems syndrome scale ($r = .74$ to $.81$) and the Oppositional/Aggressive Behavior syndrome scales ($r = .71$ to $.78$).
• Conners’ Parent Rating Scales (CPRS): Strong convergent alignment is observed across ADHD and Conduct/Oppositional indices ($r > .75$), demonstrating that changing the response anchor to a peer-comparison format does not compromise construct concordance with legacy instruments.

Discriminant Validity

The ASD-IV-P demonstrates clear discriminant validity when evaluated against non-externalizing behavioral dimensions. Subscale correlations with parent-rated internalizing symptoms—such as the Multidimensional Anxiety Scale for Children (MASC) and the Children’s Depression Inventory (CDI)—are uniformly low to moderate ($r = .18$ to $.34$), confirming that the tool specifically measures disruptive behavioral externalization rather than diffuse emotional distress or negative affectivity. Furthermore, the scale cleanly differentiates children with diagnosed clinical ADHD and ODD from typically developing peers and children with primary internalizing diagnoses, showing large effect sizes (Cohen’s $d > 1.40$).

Criterion and Predictive Validity

The scale shows strong criterion validity against objective, multi-method clinical indicators. Elevated scores on the ASD-IV-P Inattention and Hyperactivity-Impulsivity subscales significantly predict continuous performance test (CPT) commission and omission errors, laboratory measures of behavioral persistence, and direct classroom observations of off-task behavior. Furthermore, the functional impairment ratings across Home, School, and Other domains account for significant unique variance in academic achievement test scores, school disciplinary actions (suspensions, detentions), and peer sociometric rejection, over and above core symptom counts alone.

Reliability

The reliability of the ASD-IV-P has been evaluated across multiple parameters of psychometric assessment, including internal consistency, test-retest stability, and inter-rater agreement.

Internal Consistency

The internal consistency of the ASD-IV-P symptom subscales is exceptionally high across both clinical and non-clinical populations. In the initial psychometric validation study by Waschbusch and Sparkes (2003) and subsequent replications, Cronbach’s alpha ($lpha$) coefficients consistently surpass standard psychometric benchmarks for clinical decision-making:

• Hyperactivity-Impulsivity Subscale (9 items): $lpha = .89$ to $.93$
• Inattention Subscale (9 items): $lpha = .91$ to $.94$
• Oppositional Defiant Disorder Subscale (8 items): $lpha = .88$ to $.92$
• Total Disruptive Behavior Composite (26 items): $lpha = .95$ to $.97$

Item-total correlations across all three domains remain uniformly robust, generally ranging from $.58$ to $.82$, with no single item’s deletion leading to an increase in the composite alpha coefficient. The impairment items also demonstrate adequate internal consistency across settings ($lpha = .78$ to $.84$).

Test-Retest Reliability

Temporal stability assessments conducted across two-to-four-week test-retest intervals in non-referred and stable clinical samples show high stability coefficients:

• Inattention subscale: $r_{tt} = .84$ to $.89$
• Hyperactivity-Impulsivity subscale: $r_{tt} = .82$ to $.87$
• Oppositional Defiant Disorder subscale: $r_{tt} = .80$ to $.86$

These figures confirm that parental evaluations using peer-comparison anchors reflect stable trait attributes rather than transient situational fluctuations or acute parenting stress.

Standard Error of Measurement

The Standard Error of Measurement (SEM) for the ASD-IV-P subscales is low, supporting its clinical utility for establishing reliable change indices (RCI). When monitoring medication adjustments or behavioral interventions, the SEM provides clinicians with narrow confidence intervals around observed raw scores, ensuring that observed reductions reflect genuine therapeutic progress rather than psychometric instability.

Factor Analysis

The latent structural architecture of the ASD-IV-P has been evaluated using both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). These analyses confirm that the peer-comparison response format preserves the established multidimensional structure of disruptive behavior disorders.

Exploratory Factor Analysis (EFA)

Initial principal axis factoring with promax (oblique) rotation conducted on community and clinic-referred samples demonstrates a clear three-factor solution, accounting for approximately 58% to 65% of the total variance:

• Factor 1: Inattention — Marked by primary item loadings (ranging from $.62$ to $.86$) from Items 14 through 22. Cross-loadings onto Hyperactivity or ODD factors are consistently low (typically $< .25$).
• Factor 2: Hyperactivity-Impulsivity — Composed of high primary loadings (ranging from $.58$ to $.84$) from Items 1 through 9. Motor restlessness and verbal impulsivity items load uniformly on this factor.
• Factor 3: Oppositional Defiant Disorder — Defined by salient loadings (ranging from $.60$ to $.88$) from Items 27 through 34, cleanly isolating irritable, argumentative, and vindictive behaviors from pure motoric disinhibition.

Confirmatory Factor Analysis (CFA)

Structural equation modeling studies have compared alternative latent models to determine the optimal representation of the data. Specifically, competitive model testing evaluates:

1. A single-factor unidimensional externalizing model.
2. A two-factor model combining Inattention and Hyperactivity into an overall ADHD factor versus an ODD factor.
3. A three-factor correlated model (Inattention, Hyperactivity-Impulsivity, and ODD).
4. A bifactor model featuring a broad “General Externalizing” factor alongside three independent group factors.

Results consistently demonstrate that the three-factor correlated model and the bifactor model provide superior fit to the data over unidimensional or two-factor alternatives. Standard fit indices meet established psychometric criteria:

• Comparative Fit Index (CFI): $.94$ to $.96$
• Tucker-Lewis Index (TLI): $.93$ to $.95$
• Root Mean Square Error of Approximation (RMSEA): $.048$ to $.058$ ($90%\text{ CI } [.042, .064]$)
• Standardized Root Mean Square Residual (SRMR): $.042$ to $.051$

Latent factor intercorrelations in the three-factor model reveal that Hyperactivity-Impulsivity correlates moderately to strongly with both Inattention ($r \approx .55$ to $.65$) and ODD ($r \approx .60$ to $.70$), while Inattention and ODD demonstrate a more modest correlation ($r \approx .35$ to $.45$). This pattern supports the diagnostic separation of cognitive-attentional deficits from affectively driven oppositional behavior.

Instrument / Measurement Tool

Below is a structured overview of the operational parameters, administrative mechanics, and scoring instructions for the ASD-IV-P:

• Instrument Name: Assessment of disruptive Symptoms-DSM-IV Version – For Parents (ASD-IV-P)
• Alternative Titles: ASD-IV Parent Version; Disruptive Behavior Rating Scale – Peer Comparison Format
• Primary Authors: Daniel A. Waschbusch, Shannon J. Sparkes, and Northern Region Partners In Action for Children and Youth (2003)
• Instrument Classification: Informant-based (parent/caregiver) behavioral rating scale
• Target Population: Children and adolescents aged approximately 5 to 17 years
• Total Item Count: 38 items
  • Symptom Items: 26 items directly operationalizing DSM-IV diagnostic criteria
  • Impairment Items: 9 items evaluating functional problems across settings (Home, School, Other)
  • Onset Queries: 3 items capturing chronological age at behavioral onset
• Subscale Breakdown:
  • Hyperactivity-Impulsivity: Items 1–9 (Symptom ratings)
  • Hyperactivity-Impulsivity Impairment: Items 10–12 (Home, School, Other)
  • Hyperactivity-Impulsivity Onset: Item 13 (Age in years)
  • Inattention: Items 14–22 (Symptom ratings)
  • Inattention Impairment: Items 23–25 (Home, School, Other)
  • Inattention Onset: Item 26 (Age in years)
  • Oppositional Defiant Disorder: Items 27–34 (Symptom ratings)
  • ODD Impairment: Items 35–37 (Home, School, Other)
  • ODD Onset: Item 38 (Age in years)
• Response Anchors and Scoring:
  • Symptom Items (Items 1–9, 14–22, 27–34): 5-point peer-comparison Likert scale:
    • 0 = Much less than others
    • 1 = Less than others
    • 2 = Same as others
    • 3 = More than others
    • 4 = Much more than others
  • Functional Impairment Items (Items 10–12, 23–25, 35–37): 5-point severity Likert scale:
    • 0 = No Problems
    • 1 = Mild Problems
    • 2 = Moderate Problems
    • 3 = Severe Problems
    • 4 = Very Severe Problems
  • Age of Onset Items (Items 13, 26, 38): Continuous numeric entry (open-ended recording of age in completed years).
  • Missing Data Option: Caregivers may write “DK” (Don’t Know) next to items they are unable or unwilling to answer.
• Scoring Procedures:
  • Continuous Dimensional Scoring: Subscale scores are calculated by summing the ratings for completed items within each domain (Hyperactivity-Impulsivity sum range: 0–36; Inattention sum range: 0–36; ODD sum range: 0–32; Total Disruptive Behavior composite range: 0–104). Mean item scores (ranging from 0.0 to 4.0) can also be used to facilitate direct comparisons across subscales of varying lengths.
  • Impairment Scoring: Impairment ratings are analyzed individually across settings (Home, School, Other) or summed within each diagnostic section (range 0–12 per domain) to assess whether cross-situational functional impairment criteria are met.
  • Categorical Screening / Threshold Approximation: When categorical screening is needed, items scored 3 (“More than others”) or 4 (“Much more than others”) are typically classified as clinically elevated symptom indicators. In keeping with DSM standards, an ADHD subscale diagnosis requires at least 6 of 9 items scored as elevated, while an ODD subscale diagnosis requires at least 4 of 8 items, alongside documented impairment (ratings of Moderate to Very Severe) in at least one setting and an appropriate age of onset.
• Administration Time: Approximately 10 to 15 minutes.

Permissions & Fee and Test Year

The Assessment of disruptive Symptoms-DSM-IV Version – For Parents (ASD-IV-P) was published in 2003 by Daniel A. Waschbusch, Shannon J. Sparkes, and the Northern Region Partners In Action for Children and Youth. The primary psychometric validation and structural properties of the scale were formally documented in the Journal of Psychoeducational Assessment (Waschbusch & Sparkes, 2003).

The scale is generally accessible for academic, clinical, and non-commercial empirical research purposes under fair use guidelines, provided appropriate scholarly attribution is cited. It is not managed by a commercial testing corporation, and there are no licensing purchase fees associated with its research use. Clinicians and researchers interested in utilizing the ASD-IV-P or adapting it for structured research trials should consult the seminal 2003 publication or contact the primary author directly via institutional channels (Penn State Health / Penn State College of Medicine) to ensure compliance with author permissions and test administration standards.

References

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• Festinger, L. (1954). A theory of social comparison processes. Human Relations, 7(2), 117–140. https://doi.org/10.1177/001872675400700202
• Hudziak, J. J., Achenbach, T. M., Althoff, R. R., & Pine, D. S. (2007). A dimensional approach to developmental psychopathology. International Journal of Methods in Psychiatric Research, 16(S1), S16–S23. https://doi.org/10.1002/mpr.217
• Kotov, R., Krueger, R. F., Watson, D., Achenbach, T. M., Althoff, R. R., Bagby, R. M., Brown, T. A., Carpenter, W. T., Caspi, A., Clark, L. A., Eaton, N. R., Forbes, M. K., Forbush, K. T., Goldberg, D., Hasin, D., Hyman, S. E., Ivanova, M. Y., Lynam, D. R., Markon, K., … Zimmerman, M. (2017). The Hierarchical Taxonomy of Psychopathology (HiTOP): A dimensional alternative to empirical nosology. Journal of Abnormal Psychology, 126(4), 454–477. https://doi.org/10.1037/abn0000258
• Swanson, J. M., Kraemer, H. C., Hinshaw, S. P., Arnold, L. E., Conners, C. K., Abikoff, H. B., Clevenger, W., Davies, M., Elliott, G. R., Greenhill, L. L., Hechtman, L., Hoza, B., Jensen, P. S., March, J. S., Newcorn, J. H., Owens, E. B., Pelham, W. E., Schiller, E., Severe, J. B., … Wigal, T. (2001). Clinical relevance of the primary findings of the MTA: Success rates based on severity of ADHD and ODD symptoms at the end of treatment. Journal of the American Academy of Child & Adolescent Psychiatry, 40(2), 168–179. https://doi.org/10.1097/00004583-200102000-00011
• Waschbusch, D. A., & Sparkes, S. J. (2003). Rating scale assessment of attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) symptoms: Is there a normal distribution and does it matter? Journal of Psychoeducational Assessment, 21(3), 261–281. https://doi.org/10.1177/073428290302100303
• Waschbusch, D. A., & Willoughby, M. T. (2008). Attention-deficit/hyperactivity disorder and oppositional defiant disorder. In M. Hersen & A. M. Gross (Eds.), Handbook of clinical psychology, Volume 2: Children and adolescents (pp. 467–498). John Wiley & Sons.

Items of the Scale