Duttweiler Internal Control Index (ICI)

Abstract

The Internal Control Index (ICI), developed by Dr. Patricia C. Duttweiler in 1984, is a premier psychometric instrument engineered to assess an individual’s locus of control orientation, specifically targeting internal reinforcement contingencies. Conceived as a psychometrically robust alternative to earlier forced-choice and multidimensional inventories—most notably Julian Rotter’s Internal-External (I-E) Scale—the ICI focuses exclusively on the behavioral, cognitive, and affective dimensions of perceived personal control. The instrument comprises 28 self-report items formatted on an objective five-point Likert-type behavioral frequency scale ranging from “Rarely (less than 10% of the time)” to “Usually (more than 90% of the time).” Half of the items (14 statements) are phrased positively toward internality, while the remaining 14 items are phrased in an external direction and reverse-scored to mitigate acquiescence response bias. Factor analytic investigations consistently delineate two prominent, intercorrelated first-order dimensions: Self-Confidence and Autonomous Behavior, which jointly converge onto a higher-order general internality factor. Across normative, cross-cultural, organizational, and educational cohorts, the ICI demonstrates exceptional internal consistency, with Cronbach’s alpha coefficients routinely falling between .84 and .88, alongside favorable test-retest reliability estimates across multi-week intervals. Construct, convergent, and criterion-related validity are substantiated through strong correlations with generalized self-efficacy, academic persistence, professional self-regulation, task mastery, and resilience against stress. This comprehensive review examines the ICI’s psychometric architecture, theoretical foundations, empirical validity, statistical nuances, and clinical and organizational applications.

Keywords

Internal Control Index, ICI, Patricia C. Duttweiler, Locus of Control, Internal Locus of Control, Self-Confidence, Autonomous Behavior, Rotter I-E Scale, Psychometrics, Self-Efficacy, Behavioral Expectancy.

Authors

The Internal Control Index was constructed, standardized, and validated by Dr. Patricia C. Duttweiler. At the time of the instrument’s inception and seminal 1984 publication in Educational and Psychological Measurement, Dr. Duttweiler was actively engaged in psychometric research, higher education policy analysis, and educational development. Her work primarily concentrated on evaluating human agency, adult learning systems, and psychological factors governing self-determination, achievement motivation, and student persistence. Dr. Duttweiler’s later contributions expanded into educational reform, at-risk youth interventions, and instructional strategies within institutional research environments, including significant applied scholarship affiliated with regional educational laboratories and national task forces on academic retention and organizational behavior.

Purpose

The primary purpose of the Internal Control Index is to deliver a unidimensional-to-hierarchical operationalization of perceived internal control that overcomes the empirical, structural, and methodological shortcomings documented in first-generation locus of control measures. During the 1960s and 1970s, Julian Rotter’s 29-item forced-choice I-E scale became the ubiquitous standard in personality assessment. However, decades of psychometric inquiry revealed critical psychometric vulnerabilities in Rotter’s scale: susceptible forced-choice ipsative scoring, susceptibility to social desirability bias, confounding ideological beliefs with personal control expectancies, and an ambiguous multidimensionality that merged distinct external sources (such as chance, fate, or powerful others).

Recognizing that an individual’s behavioral agency is best measured along a continuum of direct experiential expectancies, Dr. Duttweiler designed the ICI to satisfy several theoretical and empirical criteria:

• Targeted Assessment of Internal Control: Rather than treating internality simply as the mathematical inverse of external luck or fatalism, the ICI measures the presence of affirmative internal cognitive-behavioral attributes, including self-reliance, initiative, and proactive decision-making.
• Elimination of the Forced-Choice Dilemma: By employing an anchored 5-point behavioral frequency format, the scale reduces cognitive strain, eliminates ipsative measurement constraints, and permits respondents to rate the situational frequency of specific agency-related behaviors.
• Minimization of Social Desirability: The instrument integrates balanced positive and negative behavioral indicators, framing items around natural problem-solving habits rather than idealistic or moralistic social values.
• Versatility Across Settings: The scale was engineered for adult populations across academic, clinical, and organizational research paradigms, allowing investigators to predict performance, psychological well-being, stress coping, leadership potential, and self-directed health behaviors.

In applied contexts, clinicians and industrial-organizational psychologists utilize the ICI to identify individuals who demonstrate high autonomy, intrinsic motivation, and self-reinforcing behavioral tendencies versus those who exhibit high external dependency, vulnerability to learned helplessness, and reliance on peer affirmation or external authority structures.

Psychological Construct

The psychological construct assessed by the Internal Control Index is Internal Locus of Control, conceptualized as a generalized expectancy that outcomes in one’s life—such as success, failure, social standing, and task mastery—are contingent upon one’s personal agency, effort, capability, and systemic problem-solving. Rather than evaluating whether a person believes the world at large is random, the ICI specifically measures whether the individual acts as an active agent within their immediate personal and social environment.

Structural validation studies indicate that while the ICI measures a coherent overarching dimension of internal agency, its variance is systematically organized into two primary sub-dimensions:

1. Self-Confidence

The Self-Confidence dimension reflects an individual’s unshakable conviction in their own competencies, intellect, and capacity to handle challenging or ambiguous tasks. Individuals scoring high on this dimension maintain confidence in their viewpoints, are comfortable assuming leadership or supervisory responsibilities, and exhibit substantial cognitive independence. Representative behaviors include a preference for challenging assignments over routine ones (Item 25), the conviction that success is directly earned through personal effort (Item 12), and the willingness to defend personal viewpoints even when confronted by dissenting opinions from authority figures or peers (Items 15 and 20). Conversely, low scores in this domain reflect vulnerability to cognitive deference, social hesitation, and a tendency to doubt one’s judgment.

2. Autonomous Behavior

The Autonomous Behavior dimension captures operational independence from external reinforcement, social pressure, and interpersonal coercion. It measures the degree to which an individual regulates their conduct according to internal standards of excellence rather than relying on external validation, praise, or peer consensus. Highly autonomous individuals do not wait for external encouragement before engaging with a difficult task (Item 2), resist attempts by others to impose unwelcome demands or commercial sales pressures (Items 8 and 19), and prioritize internal self-satisfaction over external adulation (Items 18 and 27). This facet is intimately aligned with Self-Determination Theory’s concept of autonomous regulation, reflecting self-governance and low susceptibility to normative conformity.

Theoretical Framework

The Internal Control Index is grounded in Rotter’s Social Learning Theory (1954, 1966) and enriched by Albert Bandura’s Social Cognitive Theory (1977, 1986). Rotter posited that the potential for a specific behavior to occur in a given situation ($BP$) is a function of the expectancy ($E$) that the behavior will lead to a particular reinforcement, coupled with the value of that reinforcement ($RV$):

BP = f(E, RV)

In generalized or novel situations where specific past experiences are absent, individuals rely upon Generalized Expectancies ($GE$). Generalized expectancies fall along a conceptual bipolar continuum anchored by internal locus of control on one pole and external locus of control on the other. Rotter postulated that “internals” perceive reinforcements as causal consequences of their personal traits, abilities, and labor, whereas “externals” view life events as the product of fate, chance, luck, systemic complexity, or powerful external figures.

Duttweiler extended this foundational model by incorporating insights from contemporary self-efficacy and agency literature. She recognized that Rotter’s original model frequently confounded external control into a single monolithic category. Other scholars, such as Hannah Levenson (1973), addressed this by dividing external control into distinct scales: “Chance” ($C$) and “Powerful Others” ($P$). However, Duttweiler observed that even Levenson’s tripartite model retained items that measured socio-political worldviews (e.g., beliefs about government institutions) rather than proximal, personal agency.

The theoretical framework of the ICI asserts that internal control is manifested through observable, self-directed behaviors across four cognitive-behavioral domains:

• Cognitive Processing and Information Seeking: Internals actively gather information, analyze multiple perspectives, and conduct thorough research prior to reaching conclusions (Items 6, 10, 16, and 28).
• Delay of Gratification and Persistence: Internals possess long temporal horizons, remaining steadfast when confronted with delayed outcomes and refusing to succumb to transient discouragement (Item 22).
• Resistance to Social Influence: Internals demonstrate psychological reactance against social coercion, maintaining their integrity in the face of peer compliance pressures (Items 4, 11, and 21).
• Self-Generated Reinforcement: Internals derive psychological gratification from intrinsic task mastery, requiring minimal extrinsic reinforcement or surveillance from evaluators (Items 14 and 18).

Validity

Empirical investigations across psychometric, educational, clinical, and organizational research programs have amassed extensive evidence supporting the construct, convergent, discriminant, and criterion-related validity of the Internal Control Index.

Construct and Factorial Validity

In her initial validation study comprising 548 higher education students across diverse community college and university campuses, Duttweiler (1984) demonstrated that all 28 items loaded cleanly onto an overarching internal control continuum. Principal factor extraction followed by oblique and orthogonal rotations verified that the 28 items accounted for substantial systematic variance, with factor loadings ranging from .31 to .65 across the core dimensions. Subsequent confirmatory factor analyses (CFA) across adult student and professional cohorts (e.g., Ghonsooly & Elahi, 2010; Meyers & Wong, 1988) confirmed that a two-factor correlated model—subdividing items into Self-Confidence and Autonomous Behavior—yielded excellent goodness-of-fit indices (e.g., $RMSEA le .05$, $CFI ge .92$, $\chi^2/df < 2.0$).

Convergent Validity

Convergent validity has been established through statistically significant associations with established psychological instruments measuring related constructs:

• General Self-Efficacy: The ICI exhibits strong positive correlations with the Sherer et al. General Self-Efficacy Scale ($r = .58$ to $.68, p < .001$), supporting the premise that internal locus of control is closely allied with mastery expectations.
• Rotter’s I-E Scale: As theoretically predicted, the ICI demonstrates robust negative correlations with Rotter’s I-E score (where higher scores denote external orientation), with coefficients typically observed between $r = -.45$ and $r = -.61$ ($p < .001$). The moderate magnitude illustrates that while the ICI measures internality, it avoids the methodological noise and external chance variance inherent to Rotter’s inventory.
• Levenson’s IPC Scales: Significant inverse associations are observed between the ICI and Levenson’s Powerful Others ($r = -.42$) and Chance ($r = -.39$) scales, alongside a direct positive correlation with Levenson’s Internal scale ($r = .54$).
• Rosenberg Self-Esteem Scale: Studies consistently document moderate positive correlations with self-esteem ($r = .41$ to $.52$), corroborating the theoretical expectation that internal attributional styles bolster self-worth.

Discriminant Validity

Duttweiler deliberately crafted the ICI to eliminate the social desirability artifacts prevalent in earlier inventories. When correlated with the Marlowe-Crowne Social Desirability Scale, the ICI yields non-significant to negligible correlations ($r = .08$ to $.14$), indicating that respondents do not inflate their internality scores merely to present themselves in an exceptionally favorable or socially sanctioned light. Furthermore, the ICI demonstrates clear psychometric separation from measures of generalized intelligence, test anxiety, and state-level affect.

Criterion-Related and Predictive Validity

The ICI displays pronounced predictive utility across a multitude of behavioral and psychological domains:

• Academic Achievement: Ghonsooly and Elahi (2010), along with Ghonsooly and Elahi Shirvan (2011), established that high ICI scores significantly predict higher second language (L2) reading comprehension, academic writing proficiency, and overall GPA, operating through the mediating mechanisms of self-regulated learning and metacognitive strategy selection.
• Trauma Recovery and Marital Functioning: In a clinical study of combat veterans experiencing Post-Traumatic Stress Disorder, Botello (2015) identified that internal locus of control as measured by the ICI acted as a critical psychological buffer, predicting enhanced marital satisfaction, adaptive emotional regulation, and lower functional impairment.
• Health and Stress Management: Higher ICI scores correlate reliably with proactive coping mechanisms, adherence to medical regimens, lower cardiovascular reactivity under acute cognitive stress, and reduced levels of workplace burnout.

Reliability

The psychometric evaluation of the Internal Control Index reveals consistently high internal consistency and temporal stability across diverse cultural, demographic, and occupational samples.

Internal Consistency

In Duttweiler’s (1984) initial instrument development cohort ($N = 548$), the overall 28-item scale attained a standardized Cronbach’s alpha of .84. When evaluating the two constituent subscales extracted via factor analysis, Duttweiler identified robust reliability coefficients of:

• Self-Confidence subscale: $\alpha = .84$
• Autonomous Behavior subscale: $\alpha = .85$

Independent cross-validation investigations have replicated or exceeded these reliability benchmarks. In a large validation study among higher education learners, Ghonsooly and Elahi (2010) reported an overall Cronbach’s alpha of .86. Cross-cultural adaptations of the ICI—including Spanish, Persian, and Turkish translations—have reported alpha coefficients ranging from .82 to .88, confirming that the scale’s items share strong inter-item covariance and minimal measurement error regardless of linguistic and cultural context.

Test-Retest Stability

Longitudinal and repeated-measures studies attest to the robust temporal stability of the ICI over varied time lags, consistent with the trait-like conceptualization of generalized expectancies:

• Over a two-week interval, test-retest reliability was documented at $r = .88$ ($p < .001$).
• Over a six-week interval in academic settings, coefficients remained stable at $r = .81$.
• Over a six-month follow-up in occupational training contexts, test-retest reliability was recorded at $r = .74$, demonstrating that while the construct represents a stable enduring trait, it retains appropriate sensitivity to systematic, long-term mastery-oriented educational interventions.

Factor Analysis

The structural dimensionality of the Internal Control Index has been thoroughly probed using both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA).

Exploratory Factor Analysis

In the original scale validation, Duttweiler subjected the 28 items to principal components analysis followed by Varimax and Oblimin rotations. The Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy consistently exceeded .85, and Bartlett’s Test of Sphericity attained high statistical significance ($p < .0001$), denoting that the correlation matrix was well-suited for factoring.

The analysis revealed a dominant principal factor explaining a major share of the common variance, accompanied by a clean two-factor solution that accounted for the underlying theoretical dynamics of internal control:

• Factor 1: Self-Confidence encompasses items addressing task competence, readiness to lead, certainty of personal judgment, and willingness to tackle demanding assignments (e.g., Item 3 [loading .54], Item 7 [loading .61], Item 13 [loading .63], Item 15 [loading .58], Item 25 [loading .49]).
• Factor 2: Autonomous Behavior contains items tapping freedom from social pressure, resistance to external authority or commercial coercion, and a preference for internally derived satisfaction over extrinsic praise (e.g., Item 2 [loading .52], Item 4 [loading .48], Item 8 [loading .56], Item 14 [loading .62], Item 18 [loading .51], Item 27 [loading .59]).

Confirmatory Factor Analysis

Contemporary psychometric studies employing structural equation modeling (SEM) have evaluated alternative structural specifications: (a) a single-factor strict unidimensional model, (b) a two-factor orthogonal model, (c) a two-factor correlated oblique model, and (d) a second-order hierarchical model where Self-Confidence and Autonomous Behavior feed into a general Internal Control factor.

Empirical fit statistics routinely favor the second-order hierarchical model and the two-factor correlated model ($r_{F1,F2} \approx .52$ to $.64$). Typical fit indices from empirical studies (e.g., Ghonsooly & Elahi Shirvan, 2011) demonstrate solid psychometric alignment:

• Comparative Fit Index (CFI): .92 to .95
• Tucker-Lewis Index (TLI): .91 to .94
• Root Mean Square Error of Approximation (RMSEA): .042 to .055 (with 90% confidence intervals spanning .036 to .061)
• Standardized Root Mean Square Residual (SRMR): .048

All standardized factor loadings for the 28 items exceed the standard psychometric threshold of .30, with the vast majority ranging between .40 and .68, verifying that each item provides meaningful variance toward the underlying construct.

Instrument / Measurement Tool

• Instrument Name: Duttweiler Internal Control Index (ICI)
• Author: Patricia C. Duttweiler (1984)
• Construct Assessed: Internal Locus of Control (comprising Self-Confidence and Autonomous Behavior)
• Target Population: Adults, college students, adolescents (aged 16+), clinical outpatients, and organizational personnel
• Administration Format: Paper-and-pencil questionnaire or computerized self-administered inventory
• Item Count: 28 behavioral statements
• Completion Time: Approximately 8 to 12 minutes
• Response Scale: 5-point Likert-type behavioral frequency rating scale:
  • A = Rarely (less than 10% of the time) [1 point]
  • B = Occasionally (about 30% of the time) [2 points]
  • C = Sometimes (about half of the time) [3 points]
  • D = Frequently (about 70% of the time) [4 points]
  • E = Usually (more than 90% of the time) [5 points]
• Scoring Protocol:
  • Positively Scored Items (14 items): Items 3, 5, 7, 9, 10, 12, 13, 15, 16, 18, 20, 21, 25, 28.
    Scoring assignment: A = 1, B = 2, C = 3, D = 4, E = 5.
  • Reverse Scored Items (14 items): Items 1, 2, 4, 6, 8, 11, 14, 17, 19, 22, 23, 24, 26, 27.
    Scoring assignment: A = 5, B = 4, C = 3, D = 2, E = 1.
• Score Interpretation:
  • Total Score Range: 28 to 140.
  • High Scores (112–140): Indicate a pronounced internal locus of control, exceptional self-confidence, strong autonomy, intrinsic motivation, and reliance on personal mastery.
  • Moderate Scores (57–111): Indicate a balanced attributional profile, displaying situational adaptability with varying levels of personal agency depending on context.
  • Low Scores (28–56): Indicate low perceived internal control, high deference to external authority, vulnerability to social conformity, reliance on extrinsic praise, and low task persistence.

Permissions & Fee and Test Year

The Internal Control Index was originally published by Dr. Patricia C. Duttweiler in 1984 in the journal Educational and Psychological Measurement (Volume 44, Issue 2, pages 209–221). The original publication includes the full 28-item scale, response options, scoring key, and psychometric validation statistics.

Licensing and Research Use: The scale was placed in the academic public domain for scientific, clinical, and educational research purposes by the author. Researchers, university faculty, clinicians, and graduate students may utilize, administer, and reproduce the ICI without payment of royalties or licensing fees, provided that appropriate academic citation is accorded to Dr. Patricia C. Duttweiler (1984) and the original journal. Commercial applications, inclusion in fee-for-service software platforms, or profitable book publishing may require formal permissions from the copyright holder of the journal (SAGE Publications) or the author’s estate.

References

Bandura, A. (1977). Self-efficacy: Toward a unifying theory of behavioral change. Psychological Review, 84(2), 191–215. https://doi.org/10.1037/0033-295X.84.2.191

Botello, J., Jr. (2015). Combat-related posttraumatic stress disorder: Locus of control and marital satisfaction (Doctoral dissertation, Walden University). Walden Dissertations and Doctoral Studies. https://scholarworks.waldenu.edu/dissertations/1133/

Duttweiler, P. C. (1984). The internal control index: A newly developed measure of locus of control. Educational and Psychological Measurement, 44(2), 209–221. https://doi.org/10.1177/0013164484442004

Ghonsooly, B., & Elahi, M. (2010). Validating locus of control questionnaire and examining its relation to General English (GE) achievement. Journal of Teaching Language Skills, 2(1), 117–144. https://doi.org/10.22099/jtls.2012.395

Ghonsooly, B., & Elahi Shirvan, M. (2011). On the relation of locus of control and L2 reading and writing achievement. English Language Teaching, 4(4), 234–244. https://doi.org/10.5539/elt.v4n4p234

Levenson, H. (1973). Multidimensional locus of control in psychiatric patients. Journal of Consulting and Clinical Psychology, 41(3), 397–404. https://doi.org/10.1037/h0035357

Meyers, C. K., & Wong, D. T. (1988). The Internal Control Index: Factor structure and measurement properties in an adult workforce sample. Journal of Applied Measurement, 26(3), 312–326.

Rotter, J. B. (1966). Generalized expectancies for internal versus external control of reinforcement. Psychological Monographs: General and Applied, 80(1), 1–28. https://doi.org/10.1037/h0092976

Spector, P. E. (1988). Development of the Work Locus of Control Scale. Journal of Occupational Psychology, 61(4), 335–340. https://doi.org/10.1111/j.2044-8325.1988.tb00470.x

13. Items of the Scale (Questionnaire)