Peterson Problem Checklist (PPC)

Abstract

The Peterson Problem Checklist (PPC; Peterson, 1961) is a seminal psychometric assessment instrument designed to quantify and categorize emotional and behavioral difficulties in children during kindergarten and elementary school stages (middle childhood). Developed in response to the psychoanalytic hegemony and diagnostic ambiguity characterizing early childhood psychopathology, the PPC established an empirical, dimensional approach to child behavior assessment. The checklist was constructed by extracting common referral complaints from 427 clinical dossiers at a child guidance clinic, ultimately distilling these into a standardized 58-item inventory. Informants (typically teachers or parents) evaluate each behavior using an authentic 3-point rating scale: 0 (No problem), 1 (Mild problem), and 2 (Severe problem). Early exploratory factor analytic procedures revealed a robust two-factor structure that laid the empirical foundation for modern developmental psychopathology: Conduct Problems (reflecting externalizing behaviors such as aggression, disobedience, and disruptiveness) and Personality Problems (reflecting internalizing behaviors such as social withdrawal, anxiety, feelings of inferiority, and dysphoria). Psychometric evaluations demonstrated satisfactory interjudge (interrater) reliabilities of .77 for the Conduct Problems dimension and .75 for the Personality Problems dimension, alongside a low inter-factor correlation (r = .18) demonstrating high discriminant validity and orthogonality between constructs. The PPC served as the direct precursor to major contemporary broadband rating systems, including the Revised Behavior Problem Checklist (RBPC) and the Child Behavior Checklist (CBCL), cementing its status as an enduring landmark in clinical child assessment and pediatric behavioral taxonomy.

Keywords

Peterson Problem Checklist, Conduct Problems Subscale, Personality Problems Subscale, child psychopathology, behavioral assessment, externalizing disorders, internalizing disorders, factor analysis, interrater reliability, middle childhood

Authors

The Peterson Problem Checklist was developed by Donald Robert Peterson, Ph.D. (1923–2015), an American clinical psychologist and psychometrician who served on the faculty at the University of Illinois at Urbana-Champaign and later became the founding dean of the Graduate School of Applied and Professional Psychology (GSAPP) at Rutgers University. Peterson is widely acknowledged for pioneering the Doctor of Psychology (Psy.D.) training model and for introducing multivariate behavioral rating scales into child clinical psychology. Inquiries regarding archival validation data and historical psychometric protocols are typically directed to university repositories or academic literature indexing early developmental psychopathology research.

Purpose

The Peterson Problem Checklist was devised to resolve a persistent methodological crisis in mid-twentieth-century clinical child psychology: the absence of reliable, objective, and quantifiable measures for assessing childhood behavioral deviance. Prior to Peterson's work, clinical formulations of childhood psychiatric distress relied heavily upon speculative psychodynamic formulations and adult-derived psychiatric nosologies that exhibited poor interrater agreement and negligible empirical utility. The PPC was engineered to systematically identify, classify, and measure common behavioral problems occurring during middle childhood (encompassing kindergarten through the elementary school grades, roughly ages 5 to 12).

In clinical practice, the PPC functions as a rapid, standardized triage tool and baseline assessment instrument. By surveying both overt behavioral disruptions and subjective markers of psychological distress, the instrument allows pediatricians, clinical child psychologists, and school psychologists to identify children who deviate significantly from normative developmental trajectories. The instrument facilitates differential screening across two broad symptom spaces: outward-directed disruptive actions versus inward-directed neurotic manifestations. This differentiation prevents the under-identification of quiet, internally suffering children who, in the absence of standardized behavioral inventories, are frequently overlooked in school settings in favor of overtly disruptive peers.

From an applied educational and school psychological perspective, the checklist furnishes an objective metric for classroom behavior management, academic referral documentation, and intervention monitoring. Because teachers observe children over extended intervals in structured social environments, the PPC leverages teacher reports to capture ecologically valid symptom manifestations across school contexts. Clinicians and researchers utilize the tool to establish baseline severity levels, track treatment outcomes following behavioral or psychotherapeutic interventions, and explore developmental trajectories of externalizing and internalizing symptom constellations across longitudinal paradigms.

Psychological Construct

The psychological construct evaluated by the Peterson Problem Checklist is Childhood Problem Behavior, operationalized not as an undifferentiated, unitary entity, but as a multi-dimensional domain bisected into two overarching phenotypic expressions: Conduct Problems and Personality Problems. This dual taxonomy directly anticipated the contemporary distinction between externalizing spectrum disorders and internalizing spectrum disorders.

Conduct Problems (Externalizing Dimension)

The Conduct Problems factor aggregates behavioral manifestations characterized by deficient self-regulation, behavioral undercontrol, interpersonal aggression, defiance of social and institutional rules, and environmental friction. Phenotypically, this dimension captures observable actions that directly disrupt interpersonal environments and challenge authority structures. Representative items include:

• Disobedience, insolence and Negativistic, refuses to cooperate: Reflective of oppositional, defiant stances toward caregivers and educators.
• Fighting, quarrelsome and Destructiveness in regard to his own or others' property: Reflective of physical and verbal aggression, behavioral dysregulation, and disregard for social norms.
• Restless, inability to sit still, Hyperactive, 'always on the go', and Distractibility: Reflective of motoric impulsivity, attention deficits, and executive dysfunction.
• Profane language, swearing and Disruptive, boisterous: Behavioral manifestations that overtly perturb the social or educational milieu.

In this dimension, the child externalizes psychological conflict and regulatory failure onto the external environment, inflicting distress upon teachers, peers, and parents.

Personality Problems (Internalizing Dimension)

In sharp contrast, the Personality Problems factor captures behaviors characterized by psychological overinhibition, dysphoria, affective distress, social avoidance, and somatization. Rather than creating overt disruption in the physical environment, the child internalizes distress, experiencing emotional suffering that often escapes casual observation. Representative items include:

• Feelings of inferiority, Lacks confidence, and Self-conscious, easily embarrassed: Reflective of poor self-concept, low self-efficacy, and perceived social incompetence.
• Unhappy, depressed and Crying over minor annoyances and hurts: Indicators of mood dysregulation, dysphoric affect, and emotional liability.
• Anxious, fearful, Specific fears, phobias, and Tension, cannot relax: Reflective of pervasive autonomic arousal, generalized anxiety, and maladaptive avoidance mechanisms.
• Withdrawn, sluggish, Aloof, distant, and Shy, bashful: Indicative of social reticence, behavioral inhibition, and peer detachment.
• Physical complaints (headaches, stomachaches): Reflective of somatic expressions of psychological distress without evident physiological etiology.

Theoretical Framework

The conceptual framework undergirding the Peterson Problem Checklist is rooted in multivariate empirical taxonomy and behavioral trait theory. Prior to the 1960s, psychiatric nosology as codified in early manuals (such as the original Diagnostic and Statistical Manual of Mental Disorders) reflected clinical intuition, qualitative typology, and psychoanalytic models of neurosis versus character disorder. These conceptual models presumed that surface behaviors were merely symbolic epiphenomena of deep-seated intrapsychic complexes.

Peterson (1961) broke decisively with this tradition by embracing an empirical, inductive paradigm influenced by the trait psychology of Raymond B. Cattell and Hans J. Eysenck. Under this paradigm, clinical problems are conceptualized as continuous, covariational dimensions of observable behaviors rather than discrete, qualitative categorical illnesses. By applying multivariate statistical methodologies—specifically factor analysis—to observed, documented clinical referral complaints, Peterson hypothesized that natural functional clusterings of problem behaviors would emerge directly from the observed data.

This formulation aligns with Eysenck's dimensional model of personality, wherein extraversion, neuroticism, and psychoticism represent biological and behavioral reaction norms. In Peterson's system, Conduct Problems represent the behavioral confluence of emotional instability paired with outward extraverted, aggressive energy (undercontrolled behavior), whereas Personality Problems correspond to emotional instability combined with introverted, socially inhibited withdrawal (overcontrolled behavior). This theoretical dichotomy provided an objective classification system that moved child psychopathology away from adultomorphic diagnostic constructs and anchored it firmly within observational developmental science.

Validity

The construct, factorial, convergent, and discriminant validities of the Peterson Problem Checklist have been extensively evaluated in psychometric literature:

Factorial and Construct Validity

The primary evidence for construct validity derives from replicated exploratory factor analyses. Peterson (1961) subjected correlation matrices of the items to principal-axis extraction followed by varimax orthogonal rotation across distinct samples of kindergarten and elementary school children. Two prominent, stable factors consistently accounted for the major portion of common variance. The resulting dimensions demonstrated exceptional conceptual coherence: items reflecting aggression, defiance, and hyperactivity loaded heavily onto Factor I (Conduct Problems), while items capturing anxiety, depression, social reticence, and somatic malaise loaded onto Factor II (Personality Problems). Construct underrepresentation was minimized by starting from an exhaustive pool of 427 consecutive clinical intake charts.

Discriminant Validity

A central psychometric finding supporting discriminant validity is the low intercorrelation observed between the two primary subscales. Peterson documented a Pearson correlation coefficient of only r = .18 between the Conduct Problems and Personality Problems factor scores in normal school cohorts. This near-orthogonality verified that externalizing disruption and internalizing distress represent distinct, non-overlapping dimensions of psychological functioning rather than opposite poles of a single pathological continuum. Children can exhibit severe conduct problems without prominent neurotic traits, and vice versa, although comorbidity is empirically quantifiable.

Criterion and Convergent Validity

In subsequent validation studies conducted during the 1960s and 1970s by Peterson, Herbert C. Quay, and independent researchers, the PPC exhibited robust criterion-related validity. Scores on the Conduct Problems scale differentiated clinically referred children from non-referred normative peers at statistically significant levels (p < .001). Furthermore, Conduct Problems scores demonstrated strong positive correlations with objective markers of school maladjustment, including disciplinary suspensions, office referrals, and negative peer sociometric nominations (e.g., peer rejection). Conversely, high scores on the Personality Problems subscale correlated strongly with teacher-rated social isolation, clinical diagnoses of childhood neurosis or separation anxiety, and psychophysiological indices of autonomic nervous system hyperarousal.

Reliability

The psychometric evaluation of the PPC has emphasized interjudge (interrater) reliability and internal consistency:

Interjudge / Interrater Agreement

Because the checklist relies upon external observers, quantifying the concordance between distinct informants evaluating the same child is critical. Peterson (1961) examined interjudge reliability by having two independent teachers complete the 58-item checklist for identical cohorts of elementary school children who had been under observation across shared classroom or school environments. Interjudge reliability coefficients were calculated as:

• Conduct Problems Subscale: r = .77
• Personality Problems Subscale: r = .75

These values represent high levels of interobserver concordance for behavioral checklists within educational and clinical settings, demonstrating that the operational item anchors (0 = No problem, 1 = Mild problem, 2 = Severe problem) provide adequate calibration across independent raters.

Internal Consistency and Temporal Stability

Split-half reliability analyses and subsequent Cronbach's alpha evaluations across research cohorts utilizing the Peterson inventory indicated internal consistency coefficients exceeding .85 for the Conduct Problems subscale and .80 for the Personality Problems subscale. Test-retest reliability across short test-retest intervals (2 to 4 weeks) yielded stability coefficients between .70 and .82, indicating that the behavioral traits captured by the instrument exhibit short-term temporal stability while remaining sensitive to developmental changes and therapeutic interventions.

Factor Analysis

The architectural foundation of the Peterson Problem Checklist relies directly on factor analytic methodology. In the foundational 1961 study, Peterson collected clinical referral complaints from 427 case files at a child guidance clinic. By tallying problem frequencies and eliminating idiosyncratic complaints, he isolated 58 common problem behaviors. These 58 items were administered to teachers of non-referred public school children across kindergarten and elementary grades.

Product-moment correlation matrices were generated and subjected to principal-axis factor extraction. Application of the Kaiser-Guttman criterion (eigenvalues > 1.0) and visual examination of scree plots confirmed the presence of two dominant factors that accounted for the substantial majority of the explainable variance:

Factor I: Conduct Problem

Factor I accounted for approximately 25% to 30% of the total variance across evaluated samples. Items loading substantially (> .40) onto this factor included:

• Disobedience, insolence (.74)
• Disruptive, boisterous (.71)
• Fighting, quarrelsome (.68)
• Negativistic, refuses to cooperate (.65)
• Destructiveness in regard to property (.63)
• Hyperactive, 'always on the go' (.61)
• Temper tantrums (.59)
• Profane language, swearing (.56)

Factor II: Personality Problem

Factor II accounted for approximately 18% to 22% of the total variance. Items displaying primary loadings (> .40) onto this factor included:

• Feelings of inferiority (.72)
• Lacks confidence (.70)
• Anxious, fearful (.67)
• Shy, bashful (.64)
• Unhappy, depressed (.62)
• Self-conscious, easily embarrassed (.60)
• Social withdrawal / Aloof, distant (.58)
• Tension, cannot relax (.55)

Orthogonal Varimax rotation confirmed minimal factor overlap, yielding an empirical inter-factor correlation of r = .18. This structural independence was replicated in subsequent expansions, notably leading to the Quay-Peterson Behavior Problem Checklist.

Instrument / Measurement Tool

• Instrument Name: Peterson Problem Checklist (PPC)
• Alternative / Historical Names: Peterson Behavior Problem Checklist, Peterson 58-Item Checklist
• Construct Assessed: Problem Behavior in Middle Childhood (Conduct Problems and Personality Problems)
• Author: Donald R. Peterson, Ph.D.
• Publication Year: 1961
• Instrument Type: Standardized Behavioral Rating Checklist
• Target Population: Children in Kindergarten through Elementary School (Middle Childhood, ages ~5–12)
• Informant / Rater: Primary classroom teachers, educational specialists, or clinical observers (can also be completed by parents)
• Item Count: 58 items
• Subscales / Dimensions:
  • Conduct Problems: Overt, disruptive, aggressive, and noncompliant behaviors (24 primary items).
  • Personality Problems: Covert, anxious, dysphoric, withdrawn, and neurotic behaviors (31 primary items).
  • Residual / Physical Symptoms: Miscellaneous vegetative and developmental items (e.g., enuresis, masturbation, speech defects).
• Response Format: 3-point categorical rating scale:
  • 0 = No problem
  • 1 = Mild problem
  • 2 = Severe problem
• Scoring Procedures: Informant ratings are scored directly as integers (0, 1, or 2) and summed across designated factor keys. Higher cumulative scores indicate greater behavioral deviance and clinical severity within that respective problem domain.
• Administration Time: Approximately 10 to 15 minutes.

Permissions & Fee and Test Year

The Peterson Problem Checklist was initially published in 1961 in the Journal of Consulting Psychology (now the Journal of Consulting and Clinical Psychology), published by the American Psychological Association (APA). The author released the 58 checklist items in the academic literature for research and teaching purposes. The original instrument is in the public scientific domain for scholarly, academic, and non-commercial educational use. Subsequent commercial derivatives and formal diagnostic iterations (such as the Revised Behavior Problem Checklist [RBPC] co-developed with Herbert C. Quay) are subject to proprietary copyright held by commercial test publishers. Researchers wishing to use the original 1961 PPC in academic investigations may do so by referencing the primary source publication (Peterson, 1961).

References

• Achenbach, T. M. (1966). The classification of children's psychiatric symptoms: A factor-analytic study. Psychological Monographs: General and Applied, 80(7), 1–37. https://doi.org/10.1037/h0093895
• Eysenck, H. J. (1952). The scientific study of personality. Routledge & Kegan Paul.
• Peterson, D. R. (1961). Behavior problems of middle childhood. Journal of Consulting Psychology, 25(3), 205–209. https://doi.org/10.1037/h0038994
• Quay, H. C. (1977). Measuring dimensions of deviant behavior: The Behavior Problem Checklist. Journal of Abnormal Child Psychology, 5(3), 277–287. https://doi.org/10.1007/BF00913698
• Quay, H. C., & Peterson, D. R. (1983). Interim manual for the Revised Behavior Problem Checklist. University of Miami.
• Ross, A. O. (1974). Psychological disorders of children: A behavioral approach to theory, research, and therapy. McGraw-Hill.

13. Items of the Scale (Questionnaire)