Theory of Planned Behavior Questionnaire

1. Abstract

The Theory of Planned Behavior Questionnaire (TPB Questionnaire) is a psychometric methodology and operational measurement paradigm originated by Icek Ajzen designed to assess the socio-cognitive determinants of human social behavior. Grounded in the Theory of Planned Behavior (TPB) and its predecessor, the Theory of Reasoned Action (TRA), the questionnaire operates as a modular, behavior-specific assessment architecture rather than an immutable, standardized scale. The framework systematically maps the cognitive hierarchy leading to behavioral execution, capturing both direct constructs—namely, attitude toward the behavior (instrumental and experiential evaluations), subjective norms (injunctive and descriptive social pressures), and perceived behavioral control (PBC, encompassing self-efficacy and controllability)—and behavioral intention, the proximal determinant of deliberate action. In addition, the instrument provides an elicitation-derived methodology for evaluating indirect, belief-based cognitive foundations: behavioral beliefs multiplied by outcome evaluations, normative beliefs weighted by motivation to comply, and control beliefs scaled by power of control factors.

Typically administered using seven-point bipolar adjective scales (e.g., semantic differential ratings and Likert-type formatting), the TPB Questionnaire demonstrates strong psychometric viability across hundreds of behavioral domains, including health psychology, exercise science, organizational behavior, environmental conservation, and technology adoption. Meta-analytic evaluations reveal that direct measures of attitude, subjective norm, and perceived behavioral control account for 30% to 50% of the variance in behavioral intentions, while intentions and perceived behavioral control jointly account for 20% to 40% of the variance in actual behavior. Reliability analyses consistently report high internal consistency across direct construct subscales (Cronbach’s α typically exceeding .75 to .90), with structural equation modeling verifying robust discriminant and convergent validity when operationalized under the Principle of Compatibility (matching Target, Action, Context, and Time elements).

2. Keywords

Theory of Planned Behavior, Icek Ajzen, behavioral intention, attitude toward the behavior, subjective norm, perceived behavioral control, self-efficacy, reasoned action approach, psychometrics, expectancy-value model, social cognition, behavioral prediction.

3. Authors

The theoretical framework, psychometric foundations, and standard measurement guidelines of the Theory of Planned Behavior Questionnaire were developed by:

• Icek Ajzen, Ph.D. — Professor Emeritus of Psychology, Department of Psychological and Brain Sciences, University of Massachusetts Amherst, Amherst, MA, United States. Contact: [email protected].
• Martin Fishbein, Ph.D. (Collaborator on the Reasoned Action Approach) — Formerly Harry C. Bates Professor of Communication, Annenberg School for Communication, University of Pennsylvania, Philadelphia, PA, United States (Deceased).

4. Purpose

The primary purpose of the Theory of Planned Behavior Questionnaire is to measure the psychological determinants that guide deliberate human decision-making and behavioral execution. Unlike trait-based personality inventories that conceptualize psychological dispositions as static and generalized across situations, the TPB measurement paradigm assesses situation-specific cognitive structures directed toward a clearly delineated behavior. The instrument was designed to resolve the historic attitude-behavior consistency problem in social psychology, demonstrating that general attitudes toward objects, institutions, or abstract ideals correlate poorly with specific actions unless measured at an equivalent level of specificity.

In applied clinical, public health, and behavioral medicine settings, the TPB Questionnaire is utilized to design and evaluate evidence-based interventions. By diagnosing whether a target population’s non-adherence (e.g., medication compliance, physical therapy attendance, or dietary management) is governed primarily by negative experiential attitudes, perceived absence of social endorsement, or deficits in perceived behavioral control (such as acute skill deficiencies or external impediments), intervention designers can avoid generic informational campaigns. Instead, they can formulate precision behavioral change techniques that target the specific modal salient beliefs identified via the instrument’s formative elicitation procedures.

In academic research, the instrument serves as a primary psychometric engine across organizational behavior (e.g., assessing whistleblowing, unethical business practices, managerial decision-making, and software adoption), environmental psychology (e.g., evaluating recycling, energy conservation, sustainable transit usage, and carbon-offsetting behaviors), and educational research (e.g., predicting academic persistence, class attendance, academic integrity, and continuing education enrollment). The theoretical rationale posits that human behavior is goal-directed and rational in the sense that individuals systematically process available information, anticipate the personal and social consequences of their actions, and weigh their subjective capacity to surmount logistical, cognitive, or financial barriers before forming an intention to act.

5. Psychological Construct

The TPB Questionnaire operationalizes a multidimensional cognitive architecture consisting of four core direct constructs and their underlying indirect belief-based composites:

Attitude Toward the Behavior

Attitude represents the individual’s overall degree of favorable or unfavorable evaluation or appraisal of performing the target behavior. Rather than evaluating an external object or concept, this construct measures the subjective valence of the performance itself. Psychometrically, attitude bifurcates into two distinct sub-dimensions:

• Instrumental Attitude: Cognitive, utilitarian, or functional evaluations regarding the value, utility, and wisdom of performing the behavior (e.g., valuable–worthless, harmful–beneficial, wise–foolish).
• Experiential (Affective) Attitude: Somatosensory, emotional, and hedonistic responses elicited by the direct anticipation of performing the behavior (e.g., pleasant–unpleasant, enjoyable–unenjoyable, comfortable–uncomfortable).

Subjective Norm

Subjective norm reflects the perceived social pressure exerted on an individual by significant referents to engage or not engage in the behavior. Modern structural formulations distinguish between two social forces:

• Injunctive Norms: Perceptions of what important referent individuals or groups (e.g., family, peers, physicians, supervisors) believe the person ought to do (perceived approval or moral expectation).
• Descriptive Norms: Perceptions regarding the actual, observable behavioral practices of significant others (e.g., “whether most people like me actually perform this action”).

Perceived Behavioral Control (PBC)

Perceived Behavioral Control pertains to the individual’s perception of the ease or difficulty of performing the behavior, reflecting anticipated impediments, resources, and past experience. PBC integrates two related psychological facets:

• Capacity (Self-Efficacy): Beliefs regarding personal capability, competence, and confidence in successfully executing the action despite internal or external challenges.
• Autonomy (Controllability): The extent to which performance of the action is perceived to be entirely dependent upon personal volition, free from non-negotiable structural constraints.

Behavioral Intention

Behavioral intention represents the immediate cognitive precursor to behavior, capturing an individual’s conscious readiness, subjective probability, and motivational investment to exert effort toward executing the designated target action (e.g., “I intend to / I will make an effort to”).

Indirect (Belief-Based) Cognitive Foundations

Underpinning each direct construct is an expectancy-value cognitive structure:

• Behavioral Beliefs & Outcome Evaluations: The subjective probability that behavioral execution will produce a given outcome ($b_i$), multiplied by the positive or negative affective evaluation of that specific outcome ($e_i$), producing the belief-based attitude composite: $\sum b_i e_i$.
• Normative Beliefs & Motivation to Comply: The expectation that a specific social referent endorses the behavior ($n_i$), scaled by the person’s motivation to comply with that referent’s wishes ($m_i$), forming the indirect normative composite: $\sum n_i m_i$.
• Control Beliefs & Power of Factors: The perceived presence of an enabling or inhibiting factor ($c_i$), multiplied by the perceived power of that factor to facilitate or obstruct performance ($p_i$), generating the indirect control composite: $\sum c_i p_i$.

6. Theoretical Framework

The Theory of Planned Behavior originated as an extension of the Theory of Reasoned Action, formulated by Martin Fishbein and Icek Ajzen in 1975. The TRA posited that behavioral intention is the direct antecedent of behavior, and intention is jointly determined by attitude toward the behavior and subjective norm. However, the TRA operated under the boundary condition that the target behavior must be under complete volitional control. In empirical applications, many behaviors are constrained by non-motivational factors, such as deficits in skills, opportunities, time, financial resources, or cooperation from third parties.

To overcome this limitation, Ajzen (1985, 1991) introduced the construct of Perceived Behavioral Control, drawing theoretically on Albert Bandura‘s concept of self-efficacy while preserving the expectancy-value formulation derived from Edwards and Feather. Within the TPB framework, PBC functions in two systemic pathways: First, it acts as an indirect determinant of behavior through its influence on intention, whereby individuals rarely form strong intentions to execute behaviors they perceive as unachievable. Second, to the degree that perceived behavioral control is veridical (accurately reflecting actual behavioral control), PBC serves as a direct proxy for actual control, predicting performance independently of intention whenever real-world obstacles are encountered.

A foundational psychometric axiom of the theoretical framework is the Principle of Compatibility (or Correspondence). According to this rule, all components of the questionnaire—attitude, subjective norm, perceived behavioral control, intention, and the criterion behavior itself—must be defined and measured at identical levels of specificity across four discrete elements:

1. Target: The exact entity or object toward which the action is directed.
2. Action: The explicit physical or cognitive behavior to be executed.
3. Context: The environmental, situational, or interpersonal setting in which the action occurs.
4. Time: The temporal horizon or duration over which the behavior is evaluated.

Violations of the Principle of Compatibility (e.g., using a global attitude toward “physical fitness” to predict the specific behavior of “jogging for 30 minutes on weekday mornings for the next three weeks”) inevitably attenuate bivariate correlations, leading to erroneous inferences regarding predictive invalidity.

7. Validity

The validity of the TPB Questionnaire has been established across thousands of independent empirical investigations and substantiated by extensive meta-analytic reviews.

Predictive Validity

Meta-analyses by Armitage and Conner (2001), McEachan et al. (2011), and Rich et al. (2015) confirm the exceptional predictive capacity of the instrument. Across health-related behaviors, direct measures of attitude, subjective norm, and perceived behavioral control consistently account for $39%$ to $50%$ of the variance in behavioral intentions ($R \approx .60-.71$). In turn, intention and PBC typically account for $27%$ to $36%$ of the variance in prospective objective and self-reported behavioral outcomes ($R \approx .52-.60$). In a landmark meta-analysis across 185 independent studies, Armitage and Conner (2001) demonstrated that perceived behavioral control accounted for significant additional variance in intention over and above attitude and subjective norm ($R^2$ increase of $6%$) and contributed an independent $2%$ to $12%$ increase in the prediction of observed behaviors, confirming the theoretical superiority of the TPB over the TRA.

Convergent and Construct Validity

Convergent validity is evidenced by substantial, statistically significant correlations between the indirect belief-based composites and their corresponding direct measures. Meta-analyses reveal that the correlation between the expectancy-value attitude composite ($\sum b_i e_i$) and direct attitude measures ranges from $r = .50$ to $.70$; between the normative composite ($\sum n_i m_i$) and direct subjective norm from $r = .45$ to $.65$; and between the control composite ($\sum c_i p_i$) and direct PBC from $r = .40$ to $.60$. These correlations confirm that the direct self-report ratings faithfully represent the underlying salient belief structures elicited from the target population.

Discriminant Validity

Confirmatory factor analytic (CFA) studies consistently confirm that attitude, subjective norm, perceived behavioral control, and intention constitute distinct constructs with average variance extracted (AVE) values exceeding shared variance (squared inter-construct correlations), adhering to the Fornell-Larcker criterion. Discriminant validity between self-efficacy (capacity) and controllability (autonomy) has also been substantiated, demonstrating that while these sub-dimensions correlate, their cross-loadings are minimal and they exert distinct effects depending on whether the behavior is constrained by internal competencies or external barriers.

8. Reliability

Direct measurement scales within the TPB Questionnaire exhibit excellent internal consistency reliability when constructed under standard psychometric protocols:

• Direct Attitude: Typically assessed via 4 to 6 semantic differential items, internal consistency coefficients routinely reach Cronbach’s $\alpha = .80$ to $.92$. When partitioned into instrumental and experiential components, both subscales demonstrate high internal reliability ($ge .78$).
• Direct Subjective Norm: Assessed using 3 to 5 injunctive and descriptive items, values generally range from Cronbach’s $\alpha = .72$ to $.86$. Lower values sometimes observed in early TRA studies were subsequently resolved by separating injunctive from descriptive normative indicators.
• Direct Perceived Behavioral Control: For multi-item capacity and controllability scales, Cronbach’s $\alpha$ coefficients typically fall between $.75$ and $.88$.
• Behavioral Intention: Direct multi-item measures of intention demonstrate the highest internal consistency, with $\alpha$ values routinely exceeding $.85$ to $.94$.

Test-retest stability coefficients assessed over intervals ranging from 2 weeks to 3 months consistently yield stability indices of $r = .65$ to $.85$ across static environments, confirming the temporal reliability of the measurement model in the absence of exogenous experimental interventions or substantial environmental disruptions.

9. Factor Analysis

Extensive exploratory (EFA) and confirmatory factor analyses (CFA) have confirmed the dimensionality of the Theory of Planned Behavior Questionnaire. Initial unconstrained EFA typically yields a clean four-factor solution corresponding to the direct constructs: Attitude, Subjective Norm, Perceived Behavioral Control, and Intention. When deeper hierarchical models are tested via structural equation modeling (SEM), higher-order models demonstrate excellent goodness-of-fit:

• Attitude Sub-factors: CFA verifies a two-factor second-order structure separating Instrumental Attitude (items anchored by valuable/worthless, beneficial/harmful, important/unimportant) and Experiential/Affective Attitude (pleasant/unpleasant, enjoyable/unenjoyable), with factor loadings consistently exceeding $lambda = .70$.
• Normative Sub-factors: Partitioning of Subjective Norms into Injunctive (approval/disapproval expectations) and Descriptive norms (perceptions of peer behavior) yields superior model fit indices over unidimensional specifications ($\chi^2/df < 2.5$, $\text{CFI} > .95$, $\text{TLI} > .94$, $\text{RMSEA} < .05$).
• Control Sub-factors: Factor analyses by Terry and O’Leary (1995) and Armitage and Conner (1999) confirm that PBC divides cleanly into Self-Efficacy (confidence, perceived ease, ability) and Controllability (volition, external locus, personal control), each loading uniquely onto their respective factors ($lambda > .65$) without problematic cross-loadings.

10. Instrument / Measurement Tool

The Theory of Planned Behavior Questionnaire is structured as follows:

• Test Type: Multi-construct socio-cognitive behavioral survey instrument tailored to specific behavioral targets via formative elicitation.
• Format: Self-administered paper-and-pencil, digital/web-based, or structured interview schedule.
• Direct Measures Structure: Direct subscales employ 7-point bipolar adjective scales (e.g., semantic differential ratings and Likert-type responses) measuring target behavior under the Principle of Compatibility (Target, Action, Context, Time).
• Response Scale: 7-point bipolar scales ranging from 1 to 7 (e.g., Extremely unlikely [1] to Extremely likely [7], Extremely bad [1] to Extremely good [7], or Strongly disagree [1] to Strongly agree [7]).
• Belief-Based Composite (Indirect) Scoring Rules:
  • Belief-based Attitude: Calculated using the expectancy-value formula: $A_B = \sum_{i=1}^{m} b_i e_i$, where $b_i$ represents behavioral belief strength (typically scored 1 to 7 unipolar or -3 to +3 bipolar) and $e_i$ is outcome evaluation (scored -3 to +3 bipolar).
  • Belief-based Subjective Norm: $SN = \sum_{j=1}^{n} n_j m_j$, where $n_j$ represents normative belief strength and $m_j$ represents motivation to comply.
  • Belief-based Perceived Control: $PBC = \sum_{k=1}^{p} c_k p_k$, where $c_k$ represents control belief strength and $p_k$ represents the power of the control factor.
• Direct Measures Scoring Rules: Individual items within each direct construct (Attitude, Subjective Norm, PBC, Intention) are averaged (or summed) to generate composite scale scores after reverse-scoring negatively keyed semantic anchors.

11. Permissions & Fee and Test Year

The theoretical framework of the Theory of Planned Behavior was established in 1985 and consolidated in Ajzen’s seminal 1991 paper published in Organizational Behavior and Human Decision Processes. Because the TPB represents an open-access psychometric architecture rather than a static, proprietary commercial inventory, no licensing fees or royalties are required for academic, scientific, or applied research use. Researchers are free to formulate, adapt, and validate TPB questionnaires specific to their target behaviors and populations, following the empirical construction manual outlined by Ajzen (2002, 2006) and Fishbein and Ajzen (2010). Commercial and proprietary intervention projects are permitted to implement the framework without royalty payments, provided theoretical attribution is properly credited to the original authors.

12. References

• Ajzen, I. (1985). From intentions to actions: A theory of planned behavior. In J. Kuhl & J. Beckmann (Eds.), Action control: From cognition to behavior (pp. 11–39). Springer-Verlag. https://doi.org/10.1007/978-3-642-69746-3_2
• Ajzen, I. (1991). The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50(2), 179–211. https://doi.org/10.1016/0749-5978(91)90020-T
• Ajzen, I. (2002). Constructing a TPB questionnaire: Conceptual and methodological considerations. University of Massachusetts Amherst Working Paper, 1–14.
• Armitage, C. J., & Conner, M. (1999). Distinguishing perceptions of control from self-efficacy: Predicting consumption of a low-fat diet using the theory of planned behavior. Journal of Applied Social Psychology, 29(1), 72–90. https://doi.org/10.1111/j.1559-1816.1999.tb01375.x
• Armitage, C. J., & Conner, M. (2001). Efficacy of the theory of planned behaviour: A meta-analytic review. British Journal of Social Psychology, 40(4), 471–499. https://doi.org/10.1348/014466601164939
• Fishbein, M., & Ajzen, I. (1975). Belief, attitude, intention, and behavior: An introduction to theory and research. Addison-Wesley.
• Fishbein, M., & Ajzen, I. (2010). Predicting and changing behavior: The reasoned action approach. Psychology Press. https://doi.org/10.4324/9780203838020
• McEachan, R. R. C., Conner, M., Taylor, N. J., & Lawton, R. J. (2011). Prospective prediction of health-related behaviours with the theory of planned behaviour: A meta-analysis. Health Psychology Review, 5(2), 97–144. https://doi.org/10.1080/17437199.2010.521684
• Rich, A., Brandes, K., Mullan, B., & Hagger, M. S. (2015). Theory of planned behavior and adherence in chronic illness: A meta-analysis. Journal of Behavioral Medicine, 38(4), 673–688. https://doi.org/10.1007/s10865-015-9644-3
• Terry, D. J., & O’Leary, J. E. (1995). The theory of planned behaviour: The effects of perceived behavioural control and self-efficacy. British Journal of Social Psychology, 34(2), 199–220. https://doi.org/10.1111/j.2044-8309.1995.tb01058.x

13. Items of the Scale