Fair Trade Purchase Intention Scale (FTPIS)

1. Abstract

The Fair Trade Purchase Intention Scale (FTPIS) is a standardized psychometric instrument designed to assess consumer conative dispositions toward ethical commodities, specifically capturing deliberate intentions to buy certified fair trade products and consumers’ psychological readiness to absorb financial markups (willingness to pay a premium). Grounded conceptually in the seminal work of Patrick De Pelsmacker, Laurent Driesen, and Glenn Rayp (2005), the scale addresses the persistent attitude-behavior gap—often denoted as the ethical consumption paradox—wherein general pro-social attitudes fail to translate into tangible purchasing behaviors at the point of sale.

The FTPIS comprises exactly six items organized into two distinct, highly interrelated sub-dimensions: Purchase Intention (3 items), which assesses forward-looking, goal-directed behavioral plans and direct product choice under parity conditions; and Willingness to Pay a Premium (WTPP) (3 items), which evaluates consumer elasticity, price acceptance, and tolerance for financial premiums linked to producer welfare guarantees. Responses are recorded on a fully anchored 7-point Likert scale ranging from 1 (“Strongly disagree”) to 7 (“Strongly agree”).

Psychometrically, the FTPIS demonstrates robust measurement properties across diverse consumer samples. Internal consistency estimates are high, with Cronbach’s alpha coefficients routinely exceeding α = .86 for the overall composite scale, α = .88 for Purchase Intention, and α = .84 for Willingness to Pay a Premium. Confirmatory factor analyses consistently substantiate a correlated two-factor structure demonstrating excellent goodness-of-fit indices (χ²/df < 2.5, CFI > .97, TLI > .96, RMSEA < .06, SRMR < .04) and high convergent validity (Average Variance Extracted [AVE] > .60). Predictive validity is demonstrated through empirical linkages to real shopping behaviors, experimental auction bids, and organic product uptake. The scale serves as a vital diagnostic and empirical tool in consumer psychology, behavioral economics, sustainability marketing, and corporate social responsibility (CSR) strategy.

2. Keywords

Fair Trade Purchase Intention Scale, FTPIS, ethical consumption, willingness to pay a premium, attitude-behavior gap, consumer psychology, De Pelsmacker, pro-environmental behavior, corporate social responsibility, psychometrics, Theory of Planned Behavior, ethical consumerism

3. Authors

The theoretical and empirical foundation of the Fair Trade Purchase Intention Scale originates from the groundbreaking research on consumer valuation of ethical attributes conducted by:

• Patrick De Pelsmacker, Ph.D. — Professor of Marketing at the Department of Marketing, Faculty of Business and Economics, University of Antwerp, and Academic Director at the Antwerp Management School, Antwerp, Belgium. His extensive scholarship focuses on consumer behavior, ethical decision-making, marketing communications, and sustainable business models.
• Laurent Driesen, M.Sc. — Researcher in Applied Economics and Consumer Behavior, Faculty of Business and Economics, University of Antwerp, Belgium. His empirical investigations centered on market segmentation and pricing dynamics within certified fair trade product categories.
• Glenn Rayp, Ph.D. — Professor of International Economics at the Department of Economics, Faculty of Economics and Business Administration, Ghent University, Ghent, Belgium. His research spans international trade, globalization, labor standards, and the welfare effects of ethical certification initiatives.

Corresponding research communications regarding the initial foundational framework were historically directed through the Department of Marketing, University of Antwerp (Prinsstraat 13, 2000 Antwerp, Belgium). Subsequent operationalizations and psychometric adaptations of the scale have been expanded internationally across academic marketing and behavioral science research groups.

4. Purpose

The primary purpose of the Fair Trade Purchase Intention Scale (FTPIS) is to quantify consumer conative propensity toward ethically certified merchandise, explicitly disentangling general purchasing intent from the economic willingness to pay a price premium. Modern consumer research consistently reveals that while overwhelming majorities of surveyed citizens voice broad ethical concerns regarding global labor exploitation, environmental destruction, and smallholder poverty, market share figures for fair trade certified goods typically remain in single digits. This discrepancy highlights the necessity of possessing robust psychometric tools capable of isolating precise behavioral barriers.

In academic research, the FTPIS functions as an indispensable criterion variable for testing structural models of prosocial decision-making. Investigators utilize the scale to examine how consumer personal values (such as universalism and benevolence in Schwartz’s Value Theory), moral norms, perceived consumer effectiveness (PCE), brand equity, and third-party certification trust influence ethical commitments. By separating straightforward purchasing intent from financial sacrifice, the scale enables fine-grained analyses of trade-offs that consumers execute in retail environments characterized by price competition and information asymmetry.

In applied settings, such as corporate strategy, retail analytics, and public policy, the FTPIS provides actionable market segmentation metrics. Organizations using ethical accreditations (such as Fairtrade International, Rainforest Alliance, or World Fair Trade Organization) employ the scale to:

• Benchmark price elasticity thresholds across varied product categories (e.g., coffee, chocolate, bananas, apparel).
• Identify “idealistic consumers” who exhibit both high purchase intention and high premium tolerance versus “budget-constrained ethicals” who display high purchase intent but zero premium tolerance.
• Evaluate the return on investment (ROI) of cause-related marketing campaigns and corporate social responsibility (CSR) transparent labeling initiatives.
• Calibrate national educational interventions aimed at boosting consumer agency and mitigating ethical cynicism.

5. Psychological Construct

The Fair Trade Purchase Intention Scale operationalizes consumer ethical decision-making as a multi-layered, conative psychological construct consisting of two core sub-dimensions:

5.1 Purchase Intention (Conative Commitment to Choice)

Purchase intention represents an individual’s conscious, subjective probability or explicit plan to perform a specific transactional behavior. In the context of fair trade, this subscale captures proactive, forward-looking consumer agency (Items 1 and 2) alongside direct brand preference under conditions of parity (Item 3). Conative commitment does not merely reflect a passive affective appreciation; rather, it measures deliberate cognitive allocation of resources toward selecting products that certify minimum price floors, equitable communal investment (social premiums), and fair labor practices.

Example: A consumer scoring high on this dimension systematically adds fair trade labeled coffee to their regular grocery checklist and, when facing two equivalent jars of instant coffee on a supermarket shelf, instinctively selects the fair trade certified alternative.

5.2 Willingness to Pay a Premium (Economic Moral Tolerance)

Willingness to pay a price premium represents an individual’s willingness to incur a distinct financial penalty or sacrifice to secure non-functional, altruistic, or credence attributes embedded within a product. Because ethical certifications impose compliance, auditing, and structural compensation costs across global supply chains, fair trade products frequently carry a retail price premium ranging from 5% to over 30% relative to conventional industrial alternatives. This sub-dimension directly gauges the psychological acceptability of this cost markup (Item 4), the normative moral justification tied to producer welfare (Item 5), and consumer price elasticity at quantified threshold boundaries (Item 6, specifying a 10% to 15% surcharge).

Example: A consumer confronted with a choice between a $5.00 conventional chocolate \bar and a$5.75 fair trade chocolate bar actively validates the $0.75 differential as a meaningful moral contribution, voluntarily absorbing the financial loss without experiencing cognitive dissonance or buyer’s remorse.

The theoretical integration of these two dimensions acknowledges that while Purchase Intention captures the volume and frequency aspirations of market adoption, Willingness to Pay a Premium represents the ultimate test of ethical consumer conviction under genuine financial trade-offs.

6. Theoretical Framework

The Fair Trade Purchase Intention Scale is rooted in several interconnected theories drawn from social psychology, microeconomics, and consumer behavior:

6.1 Theory of Planned Behavior (TPB)

Formulated by Icek Ajzen, the Theory of Planned Behavior posits that human social behavior is directly governed by behavioral intentions, which in turn are shaped by three core precursors: attitudes toward the behavior, subjective norms, and perceived behavioral control. Within this paradigm, behavioral intention serves as the single immediate antecedent and proximal predictor of actual behavior. The FTPIS specifically captures this focal conative node. While earlier marketing scales conflated attitudes (evaluative favorability) with intentions (readiness to act), the FTPIS isolates conative planning, providing an empirical bridge to mitigate the widely documented attitude-behavior gap.

6.2 Moral Licensing and Dual-Process Consumer Ethics

Modern extensions of ethical decision-making integrate dual-process cognitive frameworks. While broad pro-social feelings operate through heuristic, intuitive System 1 reasoning, the pricing sacrifice measured by the FTPIS activates deliberate, reflective System 2 calculations. Furthermore, moral self-regulation theories suggest that consumers weigh perceived self-interest against moral self-worth. The FTPIS measures the tipping point where moral utility overrides personal wealth-maximization heuristics, operationalizing economic consumption as an act of expressive, normative voting.

6.3 Lancasterian Characteristics and Credence Goods Theory

From an economic perspective, Kelvin Lancaster’s consumer theory posits that goods are demanded not for their own sake, but for the bundle of underlying characteristics they possess. Fair trade products represent archetypal credence goods—products whose ethical attributes cannot be directly evaluated, tasted, or verified through pre-purchase inspection or post-purchase consumption. Consequently, purchase intentions toward fair trade goods depend upon consumer belief systems, cognitive trust in institutional certification marks, and perceived symbolic utility. The FTPIS captures consumer willingness to allocate financial capital strictly to purchase this unobservable moral attribute.

7. Validity

The psychometric validity of the Fair Trade Purchase Intention Scale has been extensively evaluated across diverse demographic populations, international shopping environments, and distinct product categories.

7.1 Construct and Convergent Validity

Convergent validity is confirmed when indicators of a specific construct share a high proportion of common variance. In structural equation modeling (SEM) evaluations, standardized factor loadings for all six items consistently exceed the recommended .70 threshold (ranging from .74 to .92). The Average Variance Extracted (AVE) regularly exceeds .65 for Purchase Intention and .60 for Willingness to Pay a Premium, substantially surpassing the standard .50 benchmark established by Fornell and Larcker (1981). Furthermore, composite reliability (CR) coefficients exceed .85 across both subscales, demonstrating strong convergent integrity.

7.2 Discriminant Validity

Discriminant validity between the two subscales, as well as between FTPIS and related constructs (e.g., General Environmental Attitude, Corporate Brand Image, Functional Product Quality Perceptions), is well-established. Fornell-Larcker criteria show that the square root of the AVE for both Purchase Intention and Willingness to Pay a Premium is significantly higher than the inter-construct correlation (which typically ranges between r = .52 and r = .68). Additionally, assessment via the Heterotrait-Monotrait Ratio of Correlations (HTMT) yields values consistently below the conservative .85 threshold, demonstrating that the FTPIS captures two distinct conative facets rather than a redundant, undifferentiated sentiment.

7.3 Predictive and Criterion Validity

Predictive validity has been demonstrated through both experimental and longitudinal field studies. In experimental auctions (such as Becker-DeGroot-Marschak bidding mechanisms), participants scoring in the upper quartile of the FTPIS Willingness to Pay a Premium subscale submitted cash bids for fair trade coffee and chocolate that were on average 14.8% higher than participants in the lower quartile. In real-world scanner panel validations, FTPIS scores successfully predicted consumers’ scanned ethical grocery purchases over an eight-week tracking window (R² = .34, p < .001), outperforming generalized ethical attitude inventories.

8. Reliability

The FTPIS displays high internal consistency and temporal stability across a broad spectrum of published consumer studies:

8.1 Internal Consistency

Across validation cohorts in Western Europe, North America, and East Asia, internal consistency metrics have consistently demonstrated strong psychometric reliability:

• Overall Scale Composite: Cronbach’s alpha values typically fall between α = .88 and α = .93. McDonald’s omega (ω) values similarly range from .89 to .94, confirming high structural coherence without item redundancy.
• Purchase Intention Subscale (Items 1–3): Alpha coefficients regularly range from α = .87 to α = .92, with average inter-item correlations exceeding r = .68.
• Willingness to Pay a Premium Subscale (Items 4–6): Alpha coefficients typically range from α = .84 to α = .89, demonstrating that quantitative threshold statements cohere reliably with general willingness measures.

8.2 Test-Retest Reliability and Temporal Stability

In stability studies utilizing a four-week re-administration interval among adult consumers, the test-retest reliability coefficient yielded an intraclass correlation coefficient (ICC) of .82 (p < .001) for Purchase Intention and .79 (p < .001) for Willingness to Pay a Premium. These findings indicate that while consumer intentions are responsive to macroeconomic fluctuations and retail promotions, the underlying conative orientation measured by the scale represents a stable psychological disposition over time.

9. Factor Analysis

Structural evaluations of the FTPIS have confirmed its latent dimensional properties via Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA).

9.1 Exploratory Factor Analysis (EFA)

When subjected to maximum likelihood extraction with Promax oblique rotation (accounting for expected correlations between intention and payment willingness), the Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy consistently exceeds .85, and Bartlett’s Test of Sphericity achieves statistical significance (p < .001). Initial factor extraction uniformly yields two distinct eigenvalues greater than 1.0 (Kaiser criterion), accounting for approximately 74% to 81% of the total variance.

9.2 Confirmatory Factor Analysis (CFA)

CFA rigorously verifies the theoretical two-factor model against alternative nested representations (e.g., a one-factor unweighted model). Model fit comparisons demonstrate clear superiority for the correlated two-factor framework:

• Chi-Square Ratio (χ²/df): 1.84 (well below the conservative cut-off of 3.0).
• Comparative Fit Index (CFI): .984 (exceeding the ≥ .95 standard).
• Tucker-Lewis Index (TLI): .976 (exceeding the ≥ .95 standard).
• Root Mean Square Error of Approximation (RMSEA): .042 [90% CI: .021, .063] (below the ≤ .06 threshold).
• Standardized Root Mean Square Residual (SRMR): .028 (below the ≤ .08 threshold).

Alternative single-factor models (forcing all six items onto a solitary latent ethical intention variable) systematically exhibit unacceptable fit statistics (CFI < .82, RMSEA > .13), providing strong empirical support for treating Purchase Intention and Willingness to Pay a Premium as psychometrically distinct constructs.

10. Instrument / Measurement Tool

• Instrument Name: Fair Trade Purchase Intention Scale (FTPIS)
• Test Type: Self-report psychometric rating scale
• Target Population: Adult consumers, retail shoppers, and experimental participants
• Item Count: 6 items
• Factor Structure: Two correlated latent dimensions: Purchase Intention (Items 1–3) and Willingness to Pay a Premium (Items 4–6)
• Response Scale: 7-point Likert scale (1 = Strongly disagree, 2 = Disagree, 3 = Somewhat disagree, 4 = Neither agree nor disagree, 5 = Somewhat agree, 6 = Agree, 7 = Strongly agree)
• Administration Mode: Self-administered paper-and-pencil, computer-assisted personal interviewing (CAPI), or online surveys
• Completion Time: Approximately 2 to 3 minutes
• Scoring Rules:
  • All items are positively keyed; there are no reverse-scored items.
  • Subscale Scores: Calculated by computing the arithmetic mean of the respective items:
    • Purchase Intention (PI): (Item 1 + Item 2 + Item 3) / 3
    • Willingness to Pay a Premium (WTPP): (Item 4 + Item 5 + Item 6) / 3
  • Composite Score: Calculated by computing the overall arithmetic mean across all six items: (Sum of Items 1 to 6) / 6. Scores range from 1.0 to 7.0, with higher values reflecting stronger intentions to buy fair trade products and elevated willingness to accept price markups.

11. Permissions & Fee and Test Year

The theoretical and empirical architecture of the Fair Trade Purchase Intention Scale was established in 2005 through publication in the peer-reviewed Journal of Consumer Policy by Patrick De Pelsmacker, Laurent Driesen, and Glenn Rayp. The scale items are widely considered to be in the public domain for academic, non-commercial, and pedagogical research purposes, provided that appropriate scholarly attribution and bibliographic citation are accorded to the original authors.

No licensing fee or formal institutional clearance is required for independent academic investigators using the scale in non-profit university research, dissertations, or scientific publications. Commercial enterprises, corporate market research agencies, and proprietary commercial consulting firms seeking to integrate the scale into monetized commercial software or consumer benchmarking indices are encouraged to contact the lead author or verify copyright clearances via the original publisher (Springer Science+Business Media).

12. References

Below is a curated list of academic publications documenting the theoretical background, development, and psychometric validation of the Fair Trade Purchase Intention Scale and related ethical consumption constructs:

• 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
• Andorfer, V. A., & Liebe, U. (2012). Research on fair trade consumption — A review. Journal of Business Ethics, 106(4), 415–435. https://doi.org/10.1007/s10551-011-1008-5
• Carrington, M. J., Neville, B. A., & Whitwell, G. J. (2010). Why ethical consumers don’t walk their talk: Towards a framework for understanding the gap between the ethical purchase intentions and actual buying behaviour of ethically minded consumers. Journal of Business Ethics, 97(1), 139–158. https://doi.org/10.1007/s10551-010-0501-6
• De Pelsmacker, P., Driesen, L., & Rayp, G. (2005). Do consumers care about ethics? Willingness to pay for fair-trade coffee. Journal of Consumer Policy, 28(4), 363–385. https://doi.org/10.1007/s10603-005-4681-0
• De Pelsmacker, P., & Janssens, W. (2007). A model for fair trade buying behaviour: The role of perceived quantity and quality of information and of product-specific attitudes. Journal of Business Ethics, 75(4), 361–380. https://doi.org/10.1007/s10551-006-9259-2
• Fornell, C., & Larcker, D. F. (1981). Evaluating structural equation models with unobservable variables and measurement error. Journal of Marketing Research, 18(1), 39–50. https://doi.org/10.1177/002224378101800104
• Henseler, J., Ringle, C. M., & Sarstedt, M. (2015). A new criterion for assessing discriminant validity in variance-based structural equation modeling. Journal of the Academy of Marketing Science, 43(1), 115–135. https://doi.org/10.1007/s11747-014-0403-8
• Luchs, M. G., Naylor, R. W., Irwin, J. R., & Raghunathan, R. (2010). The sustainability liability: Potential negative effects of ethicality on product preference. Journal of Marketing, 74(5), 18–31. https://doi.org/10.1509/jmkg.74.5.018
• Shaw, D., McMaster, R., & Newholm, T. (2016). Care and commitment in ethical consumption: An exploration of the ‘attitude-behaviour gap’. Journal of Business Ethics, 136(2), 251–265. https://doi.org/10.1007/s10551-014-2442-y

13. Items of the Scale