Original Research

Multidimensional functional packaging value and purchase intention in private-label packaged food: A serial stimulus-organism-response model

Ashok R, Chiranth KM

Received: 02 Apr. 2026; Accepted: 26 July 2026; Published: 29 Aug. 2026

Copyright: © 2026. The Authors. Licensee: AOSIS.
This work is licensed under the Creative Commons Attribution 4.0 International (CC BY 4.0) license (https://creativecommons.org/licenses/by/4.0/).

Abstract

Background: Packaging serves as a key inferential cue in private-label retail contexts, where brand-based quality signals are limited. However, existing research largely focuses on discrete packaging attributes, offering limited theoretical insight into packaging as a higher-order multidimensional construct within the stimulus–organism–response (S-O-R) framework. This study conceptualises functional packaging value (FPV) as an integrated stimulus and examines its role in shaping consumer evaluation and purchase intention through cognitive-affective pathways.

Aim: This study conceptualises FPV as a multidimensional higher-order construct within the S-O-R framework and examines its influence on the purchase intention of private-label packaged foods through the sequential mediating roles of perceived value and attitude.

Setting: This study was conducted among urban Indian consumers who recently bought private-label packaged foods in organised retail settings.

Method: A structured questionnaire with a quantitative cross-sectional design was used in this study. Data from 557 consumers were analysed using SEM modelling.

Results: FPV enhances perceived value, which reinforces attitudes and purchase intentions. FPV also directly influences attitudes, indicating complementary partial mediation through cognitive-affective pathways. The findings demonstrate that functional packaging operates as a higher-order integrated stimulus rather than a set of isolated attributes.

Conclusion: Multidimensional FPV influences purchase intention through sequential cognitive and affective processes for private-label products.

Contribution: This study reconceptualises FPV as a higher-order multidimensional construct within the S-O-R framework and demonstrates that perceived value and attitude sequentially mediate the relationship between FPV and purchase intention, extending FPV theory to an under-represented emerging private-label retail context.

Keywords: functional packaging value; private-label brands; stimulus-organism-response; perceived value; attitude; purchase intention; PLS-SEM; retail marketing.

Introduction

Functional packaging cues serve as critical external indicators in consumer evaluations, particularly for fast-moving consumer goods (FMCG), in which intrinsic product attributes cannot be fully examined prior to consumption (Shukla, Misra & Singh 2023; Steiner & Florack 2023; Underwood 2003). In private-label packaged foods, brand names and quality indicators tend to be less prominent. Therefore, consumers rely on packaging to judge product value, safety, and usability (Álvarez-González et al. 2024; Hwang & Kim 2022; Mladenovic, Van Trijp & Piqueras-Fiszman 2024). While prior research has examined individual packaging cues, such as colour, material, eco-labels and design elements (Granato, Fischer & Van Trijp 2022; Hallez et al. 2024), these studies yield inconsistent findings, some demonstrating strong cue effect on perceived quality, other showing minimal influence depending on product category and consumer familiarity, thereby revealing the limitations of a single-attribute approach and the need for an integrated system perspective (Balatsas-Lekkas, Luomala & Pennanen 2024; Steiner & Florack 2023). Although multidimensional packaging constructs exist in prior literature (Dopico-Parada, López-Miguens & Álvarez-González 2021), it is distinct in that it integrates protection, convenience, portability, information, branding, sustainability and economy into a single higher-order formative structure, rather than treating dimensions as parallel independent constructs. Despite this theoretical advance, functional packaging value (FPV) has not been positioned as a unified stimulus within a behavioural framework, leaving its mechanistic role in shaping purchase intention unresolved. Moreover, the application of such a multidimensional packaging construct within the stimulus-organism-response (S-O-R) framework is limited because prior studies have mainly focused on discrete packaging attributes rather than higher-order stimuli (Hwang & Kim 2022; Yuan et al. 2024). This limitation is particularly evident in private-label food contexts in evolving markets, where packaging serves as a compensatory quality signal. Therefore, there is a substantial gap in our understanding of how FPV, as a higher-order multidimensional construct, influences purchase intention through a structured cognitive-affective pathway. The S-O-R model offers a systematic theoretical foundation for linking multidimensional packaging stimuli with both cognitive and emotional affective responses (Hussain et al. 2023). In this model, external stimuli activate internal cognitive and affective states, which subsequently shape behavioural intentions (Su & Wang 2024). While prior research has applied the S-O-R model to individual packaging cues, no study has theorised validated higher-order FPV constructs as an integrated stimulus within this framework, nor established the sequential cognitive-affective pathway through which it drives purchase intention. To address this gap, the present study integrates FPV as a higher-order stimulus within the S-O-R framework, proposing that perceived value (cognitive) and attitude (affective) sequentially mediate FPV’s influence on purchase intention for private-label packaged foods in India. This framework responds directly to calls for theory-driven, integrated approaches to packaging research in emerging retail markets. Accordingly, this study aims to conceptualise FPV as a higher-order multidimensional construct within the S-O-R framework and examine its influence on purchase intention through the sequential mediating roles of perceived values and attitude in a private-label packaged food context.

The study addresses the following research questions:

RQ1: To what extent does FPV operate as a higher-order stimulus influencing purchase intention in private-label packaged foods?

RQ2: How do perceived value (cognitive) and attitude (affective) sequentially mediate the relationship between FPV and purchase intention?

RQ3: Does FPV exert both direct and indirect effects on purchase intention within the S-O-R framework in an emerging market context?

This study applied structural equation modelling to examine survey data from urban Indian consumers who had newly purchased private-label products. By theorising FPV as a higher-order integrated stimulus within the S-O-R framework, this research advances understanding of how packaging performance drives behavioural outcomes. For managers, these findings offer actionable guidance for private-label product design and retail positioning strategies in price-sensitive emerging markets.

Literature review

Functional packaging and consumer behaviour

In FMCG markets where customers cannot inspect products before buying, packaging is used as the primary method to determine product quality (Hajduk et al. 2024). Consumers use functional packaging as a guide to make buying decisions when they cannot assess the basic qualities of food products, like taste, freshness and safety, at the time of purchase (Obersteiner et al. 2021). The primary role of packaging involves two functions: product protection and storage, and packaging simultaneously serves as a means to transmit product information and to show product quality and shape consumer perceptions of the product (Liu et al. 2025). Packaging elements, such as structural design, materials, colour and typography, affect how consumers direct their attention, judge product quality and make buying decisions (He & Lv 2022). Research on packaging must study packaging performance as a complete system because present studies have only focused on individual packaging characteristics. This limitation exists because products in private-label environments typically have lower brand equity and lack established reputation signals (Hwang & Kim 2022). In such situations, packaging is designed to act as a barrier, reducing perceived risk and building trust among consumers. (Bronnenberg, Dubé & Sanders 2020). Research shows that the perception of similarity towards national brands is more favourable in well-designed packaging, representing a better chance of purchase (Shukla et al. 2023). The growing demand for private-label products in developing markets, such as India, requires packaging solutions that enable product differentiation, particularly in the packaged food sector, which must establish safety standards and maintain product freshness while building consumer confidence (Garg, Narwal & Kumar 2024). These results show that packaging serves as an important quality indicator that reduces informational gaps in retail settings.

Functional packaging multidimensional construct

Previous studies on packaging have typically concentrated on specific attributes, such as colour, eco-labels, and the composition of materials (Liu et al. 2025). This method offers useful details, but it neglects how packaging assessments are connected. (Srivastava et al. 2022). Consumers usually do not believe in packaging elements individually but instead create universal evaluations in which functional features shape their overall value perceptions. To address this limitation, Dopico-Parada et al. (2021) established FPV through a multidimensional performance framework that included multiple dimensions of protection, convenience, portability, storage, information, user engagement, sustainable practices and economic productivity. Functional packaging value frames packaging as an integrated value-generation system, where all functional dimensions work collectively to deliver holistic consumer value rather than isolated attribute-level benefits. These dimensions of packaging value perception depend on functional performance, usability, informational clarity, symbolic meaning and sustainability reflections (Dopico-Parada et al. 2021). The authors argue that the functional elements are exclusive yet mutually complementary from a parallel perspective, given that they are integrated into the higher-order construct of FPV (Dopico-Parada et al. 2021). Packaging research is currently shifting to structural stimulus modelling through the implementation of systemic reframing techniques, enabling researchers to analyse remote cue environmental elements (Mladenovic et al. 2024). This study advises a fundamental framework that assists researchers to study how FPV impacts consumer cognition and shopping behaviour in retail environments

Critical evaluation of functional packaging literature

Despite the growing body of research on functional packaging, the field is characterised by notable inconsistencies and methodological limitations that warrant critical examination. A recurring tension in the literature concerns whether packaging cues operate primarily through cognitive or affective pathways. While He & Lv (2022) and Wang & Chou (2020) emphasise the cognitive role of packaging in perceived value formation, Hwang & Kim (2022) and Lisboa, Vitorino & Antunes (2022) highlight affective and sensory mechanisms as equally, if not more, influential in shaping consumer attitudes. These divergent positions reflect an unresolved theoretical debate about the sequential versus parallel nature of consumer responses to packaging stimuli, a gap that this study directly confronts rather than assumes away. Methodologically, the majority of packaging studies rely on convenience or student samples in Western or East Asian contexts (Liu et al. 2025; Steiner & Florack 2023), fundamentally limiting the generalisability of their findings to emerging retail markets such as India. More critically, studies that examine individual packaging attributes in isolation (e.g. colour, eco-labels, material) systematically fail to account for the interactive and synergetic effects of these cues, producing fragmented findings that cannot be meaningfully translated into holistic managerial practice. Although Dopico-Parada et al. (2021) addressed this limitation by developing the multidimensional FPV constructs, their external validity across diverse cultural and retail contexts remains unexplored, empirically sparse and theoretically contested. While Shukla et al. (2023) demonstrated that well-designed packaging enhances national brand similarity perception in Indian markets, the precise mechanisms through which integrated functional translate into behavioural outcomes in private-label settings remain empirically underspecified. These persistent inconsistencies expose a significant gap in the literature and establish the theoretical necessity of the present investigation.

Theoretical tension and conceptual boundaries of functional packaging value within the stimulus-organism-response framework

A central theoretical challenge in integrating FPV into the S-O-R framework concerns the conceptual boundaries between FPV and related constructs such as perceived quality, utilitarian value and holistic product evaluation. While FPV is distinguished by its multidimensional, functional orientation spanning protection, convenience, portability and sustainability (Dopico-Parada et al. 2021) differentiation from broader perceived value or product quality constructs requires sharper articulation (Sweeney & Soutar 2001) and conceptualises perceived value as encompassing functional, emotional, social and epistemic dimensions, raising the critical question of whether FPV constitutes a genuinely distinct stimulus or merely a sub-dimension of value already captured in existing framework. Failure to resolve this construct boundary risks theoretical redundancy and undermines the incremental explanatory power that this study aims to establish. The S-O-R framework, while theoretically well-suited to retail and packaging contexts (Hussain et al. 2023; Roberts-Lombard & Petzer 2021), is not without significant limitations when applied to higher-order multidimensional stimuli such as FPV. Classical S-O-R applications, rooted in (Mehrabian & Russell 1974)environmental psychology tradition, were developed for unidimensional or loosely structured stimuli such as store atmosphere, not for formative, higher-order constructs of the kind FPV represents. Extending the framework to accommodate such constructs introduces theoretical complexity the original model was not designed to resolve. Specifically, the assumption of a unidirectional stimulus-to-organism-to-response pathway is likely overly linear for FPV, given that packaging dimensions such as sustainability and branding may simultaneously elicit both cognitive and affective responses (Steiner & Florack 2023; Yuan et al. 2024). This tension between the sequential logic of S-O-R and the potentially parallel processing of multidimensional packaging cues constitutes a critical theoretical boundary condition that this study empirically interrogates. By testing both a direct path (FPV →Attitude) and an indirect serial path (FPV → perceived value → attitude → purchase intention), this study does not merely apply S-O-R; it stress-tests its explanatory limits within an integrated, higher-order retail stimulus context.

Cognitive and affective responses to packaging: Perceived value and attitude

Packaging affects consumer behaviour through cognitive and affective states. Consumers determine their perceived value through the evaluation of the benefits received against required expenses from a cognitive perspective. This element plays an essential role in the purchasing decision process (Wang & Chou 2020). While classifying food, packaging shapes perceptions about safety, health, integrity and value for money (Saintives & Meral 2024). For private-label products, which have lower brand recognition, customers use packaging elements to determine the perceived worth of products, while their cognitive assessments of value drive their purchasing choices (Bronnenberg et al. 2020). However, packaging can change consumers’ feelings towards products and brands. Eye-catching, creative and eco-friendly packaging elicits positive affective responses and enhances willingness to purchase (Lisboa et al. 2022). Favourable packaging perceptions reduce perceived risk and strengthen purchase intention (Hwang & Kim 2022). Recent research has shown that sensory and functional packaging elements affect customer attitudes, establishing a connection between cognitive value assessment and customer assessment of value (Naveen et al. 2025). According to customer evaluation models, cognitive and affective reactions may occur simultaneously; however, value-based judgement is commonly the cause of attitude formation in purchasing reactions. Cognitive appraisal of packaging performance will establish positive attitudes in the future because it functions as the main element that determines product effectiveness in private-label food products that require both functional evaluation and risk assessment. This theoretical rationale invokes the context of mediation, in which models process information in parallel. It is important to note, however, that the relationship between perceived value and attitude is not uncontested in the literature. Saintives & Meral (2024) argue that affective responses to packaging can precede and independently shape cognitive value assessment, particularly in hedonic or visually rich product categories. This directly challenges the assumed cognitive-first ordering underpinning this model and highlights the necessity of empirically testing rather than presupposing the direction of cognitive-affective sequence. Furthermore, Latip et al. (2024) demonstrate that sensory packaging elements can directly elicit attitudinal responses without passing through value appraisal, suggesting that the parallel mediation path from FPV directly to attitude (H4) is not merely supplementary but may, in certain conditions, represent the dominant processing route. These theoretical tensions are not peripheral; they constitute the central justification for this study’s dual-path design, which accommodates both sequential and direct effects and thereby enables a more rigorous and nuanced examination of how functional packaging cues operate across cognitive and affective processing routes.

Purchase intention in private-label packaged foods

Consumers’ purchase intention demonstrates their desire to purchase a specific product. Purchase intention serves as a reliable indicator of whether customers will complete the buying process (Rehman & Elahi 2024). However, it is important to critically note that the antecedents of purchase intention in private-label contexts are not uniformly agreed upon. Mookherjee et al. (2024) identify perceived value, perceived quality, informational clarity and risk reduction as primary drivers; yet these dimensions are not independent, and their relative influence varies by product category, consumer involvement and retail format, a complexity that prior research has insufficiently addressed. When packaging clearly indicates freshness, safety and integrity, consumers show a higher propensity to voluntarily shift towards private label products instead of national brands (Mishra, Malhotra & Saxena 2020). In the Indian organised retail context, heightened price sensitivity does not simply reduce quality expectation; rather, it elevates the informational and functional burden placed on packaging to communicate value credibly and efficiently. Packaging attributes function as extrinsic quality indicators in this context, creating attitudes and fostering purchase intention (Jain 2021). Theocharis and Tsekouropoulos (2025) demonstrate that the convergence of eco-friendly design, clear information elements and functional usability collectively strengthens purchase intention; yet their study does not disentangle which functional dimension exerts the strongest independent effect, a limitation this study addresses through its higher-order FPV operationalisation. Taken together, these findings reinforce the theoretical argument that packaging performance is not a monolithic predictor of purchase intention but a multidimensional stimulus whose influence is mediated through sequential cognitive and affective pathways, precisely the mechanism this study seeks to model and empirically validate.

The stimulus-organism-response framework in packaging and retail contexts

The S-O-R framework provides a structured theoretical foundation for understanding how environmental cues influence behavioural intentions (Hussain et al. 2023). In this model, external stimuli activate internal cognitive and affective organisms that influence behavioural responses. Initially, this concept was applied to store atmospherics (Roberts-Lombard & Petzer 2021). Recent research has extended the S-O-R model to packaging, sensory marketing and food retail contexts (Lee 2025). Empirical studies have shown that eco-friendly food packaging can elicit cognitive and moral evaluations that increase purchase intention (Nam 2020), and interactive and information-rich packaging enhances trust and informativeness, influencing behavioural outcomes through the S-O-R framework (Su & Wang 2024; Xiang & Liu 2024). These findings confirm the suitability of the S-O-R model for analysing packaging-induced cognitive and affective mechanisms. However, it must be critically acknowledged that the majority of these S-O-R applications treat packaging stimuli as singular or discrete cues, thereby failing to test whether integrated, higher-order packaging constructs such as FPV operate differently within the framework’s S-O-R sequence. This is a non-trivial omission: if FPV operates as a gestalt stimulus rather than a collection of individual cues, then prior S-O-R findings based on isolated packaging attributes may systematically underestimate both the strength and the complexity of packaging-induced consumer responses. Addressing this gap is therefore not merely an extension of existing work, and it represents a meaningful theoretical advancement that repositions integrated packaging performances as a higher-order behavioural stimulus within the S-O-R framework, with direct implications for how future packaging research conceptualises and tests consumer responses in emerging retail environments.

Theoretical background

Theoretical foundation: Stimulus-organism-response framework

The S-O-R framework describes how external environmental cues (stimuli) activate internal psychological states (organisms), which consequently determine behavioural responses (Donovan 1994). In consumer behaviour and retail research, S-O-R has been largely employed to understand how marketing stimuli, such as store atmospherics, sensory cues and package shape, influence cognitive evaluation and purchase-related responses (Hongsuchon, Chen & Khan 2025; Pereira et al. 2023). Although other behavioural models, like the Theory of Planned Behaviour (Ajzen 1991), conceptualise purchase intention based on attitudinal and normative mechanisms, they do not adequately explain how consumers process external product-related cues to mobilise their internal psychological responses. The current study adopts the S-O-R framework since it clearly represents environmental or product-related stimuli as drivers of cognitive and emotional states (Burton et al. 1998; Hwang & Kim 2022). In private-label retailing, packaging acts as a visible point-of-sale stimulus, making the S-O-R framework theoretically relevant. In the case of packaged foods, packaging establishes a primary external stimulus, mainly for private-label products, where brand awareness is limited. Consumers rely on packaging cues to evaluate product quality, safety, usability and value (Theben, Gerards & Folkvord 2020). Consistent with S-O-R logic, these cues firstly activate cognitive assessments (e.g. perceived value), which then shape affective assessments (e.g. attitude) and drive purchase intentions (Wen et al. 2021). This cognitive-affective sequencing provides a theoretically robust foundation for studying consumer responses to functional packaging cues.

Conceptual model and construct specification

This study applies the S-O-R model by positioning FPV as the stimulus, perceived value and attitude as sequential organism states, and purchase intention as the behavioural response (Figure 1). Functional packaging value has been established as a higher-order formative construct involving multiple functional dimensions, such as protection, convenience, portability and storage, information, branding, engagement, sustainability economy and information (Dopico-Parada et al. 2021). These dimensions together determine the overall functional value of packaging, and removing any dimension alters the conceptual meaning of FPV. Functional packaging value was determined using the validated FPV scale, ensuring conceptual and construct reliability with previous packaging research (Dopico-Parada et al. 2021). Equally, perceived value, attitude and purchase intention were theorised as reflective constructs, as their values are expressions of the essential latent variables. The model specifies a serial organism pathway in which FPV indirectly influences purchase intention through perceived value and attitude. In addition, a direct path from FPV to attitude was included to capture the direct affective influence of packaging stimuli.

FIGURE 1: Stimulus-organism-response framework.

Hypotheses development

Functional packaging value and perceived value

Functional packaging cues influence consumers’ cognitive evaluations by signalling product quality, usability, safety and related benefits. Packaging effectively addresses multiple functional dimensions, reduces uncertainty and enhances expected utility, thereby strengthening perceived value (Hwang & Kim 2022). This is particularly true in private-label food categories, where functional packaging plays a vital role in shaping value perceptions (Dopico-Parada et al. 2021; Mishra et al. 2020).

In the Indian retail context, characterised by price sensitivity and increasing private-label adoption, buyers are likely to rely heavily on functional packaging cues to estimate value for money.

H1: Functional packaging value positively influences the perceived value of privately labelled packaged foods in India.

Perceived value and attitude

Perceived value signifies a central cognitive evaluation that shapes consumers’ affective responses to a product (Rehman & Elahi 2024). When consumers perceive high value, they are more likely to form favourable attitudes, reflecting positive overall evaluations of the product (Mishra et al. 2020). This relationship is particularly evident in private-label contexts, where value judgements exert a strong influence on consumers’ emotional acceptance of retail brands.

H2: Perceived value positively influences attitudes towards private-label packaged food in India.

Attitude and purchase intention

Consumers’ attitudes about a product indicate their overall evaluation of it, which in turn predicts their likelihood of purchasing it. According to the Theory of Planned Behaviour, favourable attitudes improve the likelihood of purchase-related actions (Ajzen 1991). Packaging research demonstrates that positive attitudes formed through functional and experimental packaging cues substantially strengthen purchase intention (Hussain et al. 2023).

H3: Attitude positively influences the purchase intention of private-label packaged foods in India.

Direct effect of functional packaging value on attitude

Although FPV is conceptualised and measured as a single, functionally defined higher-order construct, its influence on attitude may operate through multiple psychological processing routes rather than through different types of packaging content. From a dual-process perspective, consumers may deliberately evaluate the functional performance of packaging attributes, forming value judgements that subsequently shape attitudes, consistent with the mediated pathway proposed in H1–H3. At the same time, functional packaging cues may also evoke immediate feelings of confidence, trust and reassurance that influence attitudes more directly, particularly in routine purchase contexts where heuristic processing is common (Evans 2008; Kahneman 2011). Accordingly, FPV is expected to influence attitude both indirectly through perceived value and directly through immediate affective responses, while remaining a single, functionally defined higher-order construct throughout.

H4: Functional packaging value positively influences attitudes towards private-label packaged food in India.

Serial mediation of perceived value and attitude

According to appraisal theory, individuals first cognitively evaluate the significance and functional implications of a stimulus before developing affective responses (Lazarus 1991). In the context of functional packaging, consumers initially assess the utilitarian value of packaging attributes, and these cognitive evaluations subsequently shape their attitudes and behavioural intentions. This theoretical sequence provides the basis for the proposed serial mediation pathway. When consumers buy store brands, they typically assess cost-benefit trade-offs before determining how they feel about them (Mishra et al. 2020). This sequential ordering aligns with S-O-R applications in affective retail settings and provides a theoretical explanation for modelling perceived value as a predecessor to attitude. Within the S-O-R framework, organism responses are often subsequent, with cognitive evaluation preceding affective responses (Donovan 1994; Donovan & Rossiter 1982). In the present model, perceived value signifies an organism’s cognitive state, whereas attitude represents its affective state. Therefore, FPV is proposed to influence purchase intention through a serial mediation process, in which FPV enhances perceived value, strengthens attitudes and leads to higher purchase intention. This clarifies whether improvements in functional packaging increase intentions through value perception, attitudinal responses or both. Contemporary S-O-R research in the food and sustainability contexts provides empirical support for such a cognitive-affective mediation mechanism (Donovan 1994; Su & Wang 2024).

H5: Perceived value and attitude serially mediate the relationship between functional packaging value and purchase intention for private-label packaged foods in India.

Methods

A quantitative, cross-sectional explanatory design was employed to validate a theoretically derived model; data were subsequently analysed using partial least squares structural equation modelling (PLS-SEM) to test the hypothesised relationship between FPV, perceived value, attitude and purchase intention. The target population comprised Indian urban consumers aged 18 and above who had purchased private-label packaged food products from organised retail outlets within the 6 months preceding data collection. The sampling frame was operationalised through two access points: registered consumer panels with verified purchase history and social media platforms frequented by urban retail consumers, specifically targeting metropolitan and tier-1 cities where organised private-label retail penetration is highest. Data were collected between December 2025 and January 2026 via a structured online questionnaire. Purposive sampling was employed to ensure respondents possessed direct and recent purchase experience with private-label packaged food products, a criterion-based approach appropriate when theoretical relevance of the sample supersedes the need for statistical representativeness (Hair et al. 2021). Respondents were screened at the point of entry using a qualifying question confirming private-label packaged food purchase within the preceding 6 months; non-qualifying responses were automatically excluded, while purposive sampling restricts generalisability across the broader and socioeconomically diverse Indian consumer population. A limitation is explicitly acknowledged, and construct validity is strengthened by ensuring that all responses reflect genuine consumption experience rather than hypothetical evaluations; of 689 responses received, cases exhibiting more than 10% missing data, zero variance response patterns or statistically improbable completion times were systematically eliminated, yielding 557 valid responses for analysis, representing an effective retention of 80.8%. The sample size of 557 exceeded the minimum requirements for PLS-SEM with higher-order formative constructs and serial mediation pathways (Hair et al. 2021; Sarstedt, Ringle & Hair 2017). Constructs were measured using validated multi-item scales systematically adapted to the private-label packaged food context. The adaptation process involved three stages: firstly, items wording was revised to reflect private-label food consumption scenario while preserving the original semantic meaning of validated scales; secondly, content validity was assessed through expert review conducted by three academics specialising in consumer behaviour and retail marketing, who evaluated items’ relevance, clarity and contextual appropriateness; thirdly, a pilot study was conducted with 42 Indian urban retail consumer to assess items comprehension, internal consistency and response time prior to full-scale deployment. Minor wording refinements were made following pilot feedback before the final instrument was administered. Functional packaging value was operationalised as a higher-order formative construct with eight first-order reflective dimensions: protection, convenience, portability and storage, information, branding, engagement, sustainability and economy (Dopico-Parada et al. 2021). Perceived value, attitude and purchase intention were operationalised as reflective constructs (Ajzen 1991; Sweeney & Soutar 2001). Items were rated on a seven-point Likert scale. All constructs were modelled as reflective, except for FPV, which was specified as a higher-order formative construct. The structural model used PLS-SEM in R (version 4.5.2) and the SEMinR package. A two-stage approach was used to estimate the higher-order FPV construct (Becker, Klein & Wetzels 2012). Bootstrapping with 5000 resamples was used to assess the path coefficients, outer weights and indirect effects. Reflective measurement models were evaluated using indicator loadings, reliability measures and discriminant validity using the heterotrait-monotrait ratio (HTMT) ratio (Henseler, Ringle & Sarstedt 2015). Multicollinearity and outer weights were assessed for the formative constructs (Hair et al. 2021). Common method variance was assessed using full collinearity variance inflation factors (VIFs) (Kock 2017; Lindell & Whitney 2001). The structural model assessment included collinearity, path coefficients, R², effect sizes, predictive relevance and bootstrapped confidence intervals (Nitzl, Roldan & Cepeda 2016; Zhao, Lynch & Chen 2010). Common method bias (CMB) was addressed through both procedural and statistical remedies. Procedurally, anonymity was guaranteed, item instructions were unambiguous, and predictor and criterion constructs were deliberately separated across survey sections to minimise artificial covariation (Podsakoff, MacKenzie & Podsakoff 2003). Statistically, CMB was assessed using the full collinearity VIF approach recommended for PLS-SEM (Kock 2017), supplemented by Harman’s single factor test as a conservative cross-validation check. Full collinearity VIF values are from 1.89 to 3.76; although one value marginally exceeds the conservative threshold of 3.3, all values remained below the liberal threshold of 5.0, which is acceptable in models with high conceptual complexity (Hair et al. 2021), indicating that CMB is unlikely to threaten the validity of the findings.

Methodological limitations warrant explicit acknowledgement

Firstly, the cross-sectional design precludes causal inference. While the serial cognitive-affective pathway is theoretically grounded in S-O-R logic, the observed relationship reflects associative rather than directional evidence. Longitudinal panel designs or experimental manipulations of specific FPV dimensions would enable stronger temporal and causal claims in future research. Secondly, online recruitment introduces three distinct sampling biases. Self-selection bias may arise where respondents with stronger packaging involvement disproportionately participate. Panel bias may occur as registered panel members tend to differ behaviourally from general consumers. Platform bias is evident in the overrepresentation of digitally active metropolitan consumers. Collectively, these biases may tend to overestimate the magnitude of FPV effects, particularly among design-sensitive segments, though the extent of this potential overestimation cannot be precisely quantified without a comparative probability sample. Thirdly, despite procedural and statistical remedies, reliance on self-reported data from a single time point may not fully eliminate CMB. The controls employed reduce rather than resolve this concern, and findings should be interpreted accordingly. Fourthly, operationalising FPV as a higher-order formative introduces specification sensitivity. The non-significant outer weight observed for protection, information, branding and sustainability dimensions suggests possible context-specific construct boundaries that future research should empirically interrogate across diverse retail and cultural settings.

Ethical considerations

Ethical clearance to conduct this study was obtained from the Visvesvaraya Technological University Research Ethics Committee (No. VTU/MYS/MBA/2025/26/81). Informed consent was obtained electronically prior to participation, with respondents assured of confidentiality, voluntary participation and the right to withdraw. All data were anonymised and used solely for academic purposes, and only participants aged 18 years or above were included.

Results

Sample characteristics

The final sample consisted of 557 participants. Male respondents accounted for 60.5% of the sample, whereas female respondents accounted for 39.5%. The sample was young, with 57.1% aged between 18 years and 24 years and 80.6% aged below 35 years. Educational attainment was high, with 36.1% holding undergraduate degrees and 33.6% possessing postgraduate qualifications. Monthly income levels vary across categories: 28.0% reported earnings below ₹15 000.00, 19.6% reported between ₹15 001.00 and ₹30 000.00, 17.2% reported between ₹30 001.00 and ₹50 000.00, 7.9% reported between ₹50 001.00 and ₹75 000.00, 5.4% reported ₹75 001.00 and above, and 21.9% preferred not to disclose their income.

Measurement model assessment

Internal consistency reliability was measured using Cronbach’s alpha (α), composite reliability (CR) and rho\_A (ρA) (Hair et al. 2021; Henseler et al. 2015). All reflective constructs surpassed the recommended threshold of 0.70 (Table 1) (Hair et al. 2021; Sarstedt et al. 2017), with α ranging from 0.904 to 0.967, CR ranging from 0.940 to 0.972 and ρA ranging from 0.905 to 0.968, indicating satisfactory internal consistency and reliability. Convergent validity was valued using average variance extracted (AVE), and all constructs exceeded the suggested threshold of 0.50 (Hair et al. 2021). The AVE values ranged from 0.762 to 0.883 for the FPV dimensions and from 0.840 to 0.879 for the reflective constructs of perceived value, attitude and purchase intention. The insightful indicator loadings were statistically significant and above 0.70, ranging between 0.818 and 0.947, thereby associating indicator reliability and convergent validity (Hair et al. 2021). The outcome of the measurement model estimation is presented in Table 1. The measurement model was evaluated in accordance with the established process for PLS-SEM of reflective and formative constructs. The measurement model is shown in Figure 2.

FIGURE 2: Hierarchical model of functional packaging value as a higher-order formative construct.

Discriminant validity

Discriminant validity was evaluated using the HTMT ratio, Fornell–Larcker criterion and cross-loading (Dijkstra & Henseler 2015; Hair et al. 2021). All HTMT ratios fell below the 0.90 threshold, ranging from 0.581 to 0.866, with the highest values observed between attitude and perceived value (0.866), confirming construct distinctiveness through the model.

The Fornell–Larcker criterion confirmed discriminant validity, as the square root of each construct’s AVE exceeded its highest inter-construct correlation (Table 2). The most proximal constructs, perceived value (√AVE = 0.916) and attitude (√AVE = 0.938), yielded a correlation of 0.810, remaining well below both diagonal values (Fornell & Larcker 1981). All indicator level and all items loaded substantially higher on their intended constructs (range: 0.819–0.947) than on any other construct in the model (Table 3), providing unambiguous indicator-level evidence of discriminant validity (Hair et al. 2021).

Higher-order formative construct assessment

Functional packaging value was modelled as a higher-order formative construct, using a two-stage approach (Becker et al. 2012). Prior to second-stage estimation, outer loadings of all eight first-order reflective constructs were examined. Loadings ranged from 0.843–0.894 (Protection), 0.873–0.912 (Convenience), 0.875–0.924 (Portability), 0.819–0.908 (Information), 0.882–0.933 (Branding), 0.904–0.922 (Engagement), 0.878–0.916 (Sustainability) and 0.936–0.947 (Economy), all exceeding the 0.70 threshold (Hair et al. 2021). Composite reliability (rhoC:0.940–0.972) and AVE (0.762–0.883) confirmed robust measurement properties at the lower-order level. Multicollinearity among first-order dimensions was measured utilising VIF. The VIF values ranged from 3.12 to 4.24, which were lower than the suggested threshold of 5.0 (Hair et al. 2021; Sarstedt et al. 2017). Formative indicator weights were considered using bootstrapping with 5000 resamples. The results indicated that economy (weight = 0.436, p < 0.001), engagement (weight = 0.338, p < 0.001), convenience (weight = 0.174, p = 0.022) and portability and storage (weight = 0.155, p = 0.027) significantly contributed to FPV, as shown in Table 4. In contrast, protection, information, branding and sustainability exhibited non-significant weights. However, these dimensions were retained because formative indicators represent distinct conceptual facets of the construct and should not be removed based solely on statistical significance. The hierarchical structure of FPV is presented in Figure 3. The higher-order formative FPV constructs were evaluated using indicator relevance (outer weight), multicollinearity diagnostics (VIF:3.12–4.24) and theoretical specification, consistent with established PLS-SEM guidelines (Hair et al. 2021; Sarstedt et al. 2017).

FIGURE 3: Structural model with standardised path coefficients.

Common method bias

To assess CMB, both procedural and statistical remedies were employed. Procedural measures included anonymous participation, clear instructions and psychological separation of measurement items across constructs (Podsakoff et al. 2003). As an initial diagnostic, Harman’s single-factor test was conducted, with the single factor accounting for 58.5% of total variance. As this test is recognised as limited when used as a standalone diagnostic (Podsakoff et al. 2003), the full collinearity VIF approach, considered more robust and appropriate for PLS-SEM, was additionally applied (Kock 2015, 2017). All VIF values remained below the threshold of 5.0, with the conservative benchmark of 3.3 noted for reference. Collectively, this result suggests that CMB is unlikely to pose a serious threat to the validity of the findings.

Structural model assessment

The structural model was evaluated using a bootstrapping procedure with 5000 resamples to measure the significance of the hypothesised relationships, following the established PLS-SEM guidelines (Hair et al. 2021). Prior to hypothesis testing, collinearity among the predictor constructs was reviewed using VIF. All inner VIF values were below the suggested threshold of 5.0, representing that multicollinearity was not a concern in the structural model. Overall model fit is evaluated using the standardised root mean square residual (SRMR), which is the primary goodness-of-fit index applicable in PLS-SEM (Henseler et al. 2015). The SRMR quantifies the average discrepancy between the observed and model-implied correlations, with values below 0.08 considered indicative of acceptable model fit (Hair et al. 2021). The obtained SRMR value of 0.061 fell comfortably within this threshold, providing evidence that the proposed structural model adequately represents the relationships observed in the data. To further characterise the nature of mediation, the variance accounted for (VAF) was computed as a supplementary heuristic, following Hair et al. 2021; Zhao et al. (2010). Variance accounted for, defined as the ratio of the indirect effect to the total effect, indicates partial mediation when values fall between 20% and 80% and full mediation when values exceed 80%. For the serial pathway (FPV →Perceived Value →Attitude →Purchase Intention) and the FPV →Attitude Pathway, both VAF values of 69.8% (0.351/0.503 and 0.479/0.686, respectively) fall within the partial mediation range, consistent with the presence of significant direct and indirect effects across both pathways (Table 6). These findings suggest that while the sequential cognitive-affective pathway accounts for a substantial portion of FPV’s influence, a significant direct effect on attitude remains, supporting the complementary partial mediation interpretation within the S-O-R framework (Donovan 1994; Su & Wang 2024).

The bootstrapping results in Table 5 show that all hypothesised direct relationships are positive and significant. As the 95% confidence intervals for all paths exclude zero, H1–H4 are supported. The structural model is shown in Figure 3. The explanatory power of the structural model was calculated using the R² coefficient. Functional packaging value described 52.6% of the variance in perceived value (R² = 0.526), implying moderate power. Perceived value and FPV explained 67.6% of the variance in attitude (R² = 0.676), showing significant capability. Attitude described 53.7% of the variance in purchase intention (R² = 0.537), showing moderate power. The effect sizes (f²) measured the contribution of each predictor construct (Hair et al. 2021). The outcomes exposed large effects of FPV on perceived value (f² = 1.111) and attitude on purchase intention (f² = 1.161). Perceived value had a medium-to-large effect on attitude (f² = 0.637); however, FPV had a small effect on attitude (f² = 0.063). Significant f² values indicate that FPV and attitude are influential explanatory drivers. Predictive relevance was assessed using Stone-Geisser’s Q² criterion through blindfolding (GEISSER 1974). The Q² values were 0.439 for perceived value, 0.592 for attitude and 0.454 for purchase intention. All Q² values above zero indicated satisfactory extrapolative relevance. Serial mediation was considered using bootstrapped specific indirect effects (5000 resamples) following PLS-SEM techniques (Nitzl et al. 2016). The indirect and total effects are presented in Table 6.

The significant direct and indirect effects revealed complementary partial mediation, demonstrating that FPV influences purchase intention both directly and indirectly through sequential cognitive-affective mechanisms, as shown in Table 6. The significant serial pathway further supports the proposed cognitive-affective ordering within the S-O-R framework.

Discussion

Packaging has a strong influence on perceived value, indicating that in a private-label retail environment, where brand equity is absent, consumers actively recruit functional packaging cues as cognitive indicators for product quality and anticipated utility. This aligns with Hwang and Kim (2022), who demonstrated that packaging design shapes value perceptions in private-label contexts; however, the effect magnitude observed here appears stronger than that typically reported in attribute-specific studies (He & Lv 2022; Lisboa et al. 2022). The sequential cognitive-affective pathway reflects a psychologically grounded processing logic rather than merely a statistical mediation pattern. In routine grocery contexts, consumers tend to engage in heuristic rather than elaborative processing (Kahneman 2011), using integrated packaging values as a consolidating cognitive signal that efficiently transfers into attitude formation. This tendency is amplified in private-label settings, where the absence of brand reputation leaves consumers with no trusted evaluation anchor beyond packaging itself (Bronnenberg et al. 2020). Therefore, the sequential pathways capture a specific consumer psychology that would be obscured by single-attribute packaging studies or models that bypass the perceived value stage entirely. The strong relationship between attitude and purchase intentions reflects the attitude-behaviour consistency principle embedded within the Theory of Planned Behaviour (Ajzen 1991). When packaging successfully consolidates functional value into a favourable overall evaluation, that attitudinal summary acts as a behavioural readiness state, reducing deliberation costs and lowering psychological barriers to purchase commitment. In the private-label food context, where brand familiarity cannot function as a pre-formed attitudinal anchor, packaging-induced attitudes carry a disproportionate predictive burden, substituting for brand loyalty as a proximal driver for purchase intention. This explains why the Attitude → Purchase Intention path emerges as one of the strongest in the structural model, not because attitudes universally dominate purchase decisions, but because in low brand equity retail contexts, they represent the primary consolidating evaluation available to the consumer. The significant direct path from FPV to attitude, independent of perceived value, is theoretically explicable through system-1 processing within dual-process theory (Evans 2008; Kahneman 2011). Certain packaging dimensions, particularly tactile engagement and economic transparency, trigger fast, automatic affective responses that bypass deliberate cost-benefit appraisal entirely. Consistent with the findings of Latip et al. (2024) and Steiner and Florack (2023), sensory and functional packaging elements can directly elicit attitudinal response without passing through value appraisal, suggesting that this direct affective path is not merely supplementary but may, under conditions of low elaboration, represent the dominant processing route. This coexistence of a serial cognitive-affective path and the direct affective path therefore reflects a dual-process packaging evaluation architecture, a theoretically meaningful pattern that single-mediation models risk overlooking entirely. The nonsignificant outer weight of protection, information, branding and sustainability dimensions indicates that FPV’s explanatory power in India’s organised private-label retail context is disproportionately concentrated in economy and engagement dimensions. This suggests a context-specific hierarchy of functional salience: in price-sensitive emerging markets, economic utility and tactile interaction appear to dominate packaging evaluation, while sustainability and branding remain subordinate criteria. This represents a meaningful boundary condition of FPV’s dimensional structure that future research should empirically examine across product categories and cultural settings. These findings question the atomistic assumption underlying prior packaging research, which assumes that functional attributes operate independently and can be studied in isolation. The explanatory power demonstrated here indicates a property of FPV’s integrated multidimensional structure: no single dimension appears sufficient to drive consumer responses, and the nonsignificant individual weights of protection and information confirm that consumer evaluation is systemic rather than additive. This highlights a shift in the fundamental unit of analysis in packaging research from attributes to systems, with implications for measurement design, theoretical model construction and managerial practice. Rather than confirming the S-O-R framework straightforwardly, these findings reveal its limitations when applied to higher-order product-embedded stimuli. Classical S-O-R logic (Donovan & Rossiter 1982) assumes a unidirectional sequential pathway originally developed for ambient, unidimensional environmental stimuli, such as store atmosphere. However, FPV simultaneously activates both cognitive value appraisal and direct affective engagement, as evidenced by the coexistence of the serial indirect path and the significant direct FPV →Attitude path. This dual activation pattern is consistent with dual-process theory (Evans 2008; Kahneman 2011), in which multidimensional packaging stimuli stimulate both deliberative system-2 processing, evident in the cognitive value appraisal route, and automatic system-1 processing, evident in the direct affective response to packaging cues such as engagement and economy. This dual-process pattern indicates that the assumption of strictly sequential processing may be insufficient when applied to multidimensional formative constructs, pointing towards a modification rather than a replacement of the S-O-R framework in the product-embedded retail contexts. As reported in the structural model assessment (Table 6), both pathways fall within the partial mediation range, confirming that the sequential cognitive-affective route accounts for a substantial but not exclusive portion of FPV’s influence on purchase intention. The persistence of a significant direct effect on attitude along the serial indirect path supports a complementary partial mediation interpretation within the S-O-R framework (Donovan 1994; Su & Wang 2024), one that accommodates parallel cognitive and affective processing rather than assuming a strictly linear stimulus-to-response sequence. The findings have several actionable implications for private-label retailers and packaging managers operating in emerging retail markets. Importantly, these implications rest on a central insight: packaging should be treated as an integrated functional system rather than a collection of independent design features. Optimising individual dimensions in isolation is unlikely to generate the coherent value perceptions required to influence consumer attitudes and purchase intention. Firstly, the substantial contribution of Economy and Engagement dimensions to FPV points highlights the importance of prioritising functional utility and consumer interaction in packaging investment decisions. Retailers should ensure that packaging communicates clear value-for-money signals, such as quantity, transparency, resealability and portion efficiency, while enhancing tactile engagement through ergonomic design and intuitive opening mechanisms. These dimensions warrant greater strategic emphasis in price-sensitive private-label contexts. Secondly, the significant influence of FPV on perceived value highlights that in markets where brand equity is limited, packaging functions as a primary quality signal at the point of purchase. Retailers should therefore align packaging design with pricing strategy: premium-positioned private-label products warrant packaging that signals durability and informational richness, while value-tier products should emphasise economy and convenience cues to reinforce price-quality congruence. Treating packaging and pricing as independent decisions may create perceptual misalignment that undermines consumer trust. Thirdly, consumer responses to packaging are not uniform across segments. Price-sensitive consumers tend to evaluate packaging primarily based on functional utility and economic efficiency, whereas quality-oriented consumers place greater weight on information clarity and sustainability signals. Retailers operating across metropolitan and tier-1 markets may benefit from segment-specific packaging configurations rather than uniform strategies applied across the consumer base. Fourthly, at the organisational level, these findings imply that packaging decisions should not remain siloed within design or marketing functions. Retailers may benefit from cross-functional packaging governance by integrating insights from consumer research, supply chains and brand strategies to ensure that the economy, engagement and convenience dimensions are coherently optimised across product lines. This integrated approach is expected to yield stronger and more consistent value perceptions than ad hoc or category-isolated packaging decisions. Taken together, these findings suggest the need to reconsider three foundational assumptions in packaging and consumer research. Firstly, packaging effects may not be adequately understood at the attribute level; functional packaging operates as a system, and its consumer impact is a property of integrated performance rather than isolated cues. Secondly, the S-O-R framework, while theoretically valuable, may require conceptual modification when applied to multidimensional product-embedded stimuli: the coexistence of sequential and direct processing pathways observed here indicates that strictly linear S-O-R logic may be insufficient for higher-order formative constructs. Thirdly, the cognitive pathway, while primary, is not exclusive; packaging simultaneously activates deliberate value assessment and direct affective responses, a dual-route structure that single-mediation models risk missing entirely. Collectively, these observations advance packaging theory beyond confirmatory validation and establish FPV as a construct capable of reorienting how consumer responses to functional packaging are theorised, measured and applied in private-label retail research. The cross-sectional design restricts causal inference regarding the temporal sequencing of effects. Future studies that track changes over time or use experimental designs could better establish the sequences of events within the S-O-R model. Although statistical assessments implied limited common method variance, reliance on self-reported measures may have introduced perceptual bias. Moreover, the focus on private-label packaged foods in India limits generalisability, and replication across product categories and markets would strengthen external validity. Future research should also explore moderating variables, such as price sensitivity or sustainability orientation, to verify the boundary conditions of the observed effects.

Conclusion

This study makes a central theoretical contribution that distinguishes it from prior packaging research: it demonstrates that FPV, when modelled as an integrated higher-order construct rather than a collection of isolated attributes, exerts explanatory power over consumer purchase intention that attribute-centric approaches may underestimate. More critically, this influence operates through two simultaneous processing routes: a deliberative cognitive pathway mediated sequentially by perceived value and attitude and a direct affective pathway from FPV to attitude. This dual-process architecture suggests the need for conceptual refinement of the strictly sequential S-O-R framework when applied to product-embedded multidimensional stimuli, indicating that extension of the framework is theoretically necessary rather than merely incremental empirical refinement. These findings should be interpreted within the context of urban Indian consumers purchasing private-label packaged foods through organised retail outlets and should not be generalised to the broader Indian consumer population without further empirical validation.

Theoretical contributions

Three theoretical advancements emerged from this work. Firstly, FPV is established as a valid higher-order formative construct, wherein consumer impact is a systemic property of integrated dimensional performance, not an additive function of individual packaging cues, thus repositioning the fundamental unit of analysis in packaging research from attributes to systems. Secondly, the S-O-R framework, while theoretically productive, may be insufficient in its classical unidirectional form when applied to multidimensional product-embedded stimuli; coexistence of serial and direct processing pathways demands a dual-process extension of the framework.

Methodological limitations

Several limitations should be acknowledged. The cross-sectional survey design prevents causal inference and cannot establish temporal ordering of effects within the proposed S-O-R sequence, a particularly important constraint given that the model assumes sequential processing. The sample, drawn from organised private-label food retail consumers in India, restricts generalisability across product categories, retail formats and cultural contexts where packaging evaluation hierarchies may differ substantially. Reliance on self-reported attitudinal and intentional measures introduces potential perceptual bias and social desirability effects that experiments or observational designs would mitigate. Additionally, while common method variance was assessed statistically, the single-source, single-timepoint design cannot entirely rule out method-induced covariance in the observed structural relationships. The sample also skewed towards younger and more highly educated respondents, which may limit the generalisability of the findings to older or less-educated consumer segments within the broader private-label market.

Future research directions

Future research should prioritise three directions, each justified by a specific gap exposed by this study. Most urgently, longitudinal or experimental designs are needed to test causal directionality of the FPV →Perceived Value →Attitude →Purchase Intentions sequences; this is not merely a methodological refinement but a theoretical necessity, as the dual-process interpretation advanced here remains correlational in its current form. Secondly, cross-category and cross-market replication is required to determine whether the economy–engagement dominance observed here is specific to the price-sensitive Indian grocery context or reflects a more general pattern in emerging private-label markets, a question with direct implications for how retailers invest in packaging dimensions across portfolio segments. Thirdly, future studies should introduce theoretically grounded moderators, particularly consumer price sensitivity, sustainability orientation and private-label familiarity, to delineate the boundary conditions under which the cognitive versus affective pathways dominate, enabling more precise predictions about when packaging functions primarily as a value signal versus an affective trigger. This study contributes to a more systemic and consumer-psychology-grounded approach to packaging research by shifting attention beyond isolated attribute testing towards integrated multidimensional evaluations in private-label retail contexts.

Acknowledgements

The authors would like to thank Dr Ganesh for his valuable support in proofreading and language editing. The authors also sincerely acknowledge the valuable guidance and support of Dr Kavitha B.N. throughout the course of this research. The authors express their gratitude to all respondents who participated in the survey and contributed to this research.

The authors declare that they have no financial or personal relationships that may have inappropriately influenced them in writing this article.

Ashok R: Conceptualisation, Data curation, Formal analysis, Investigation, Methodology, Visualisation, Writing – original draft. Chiranth KM: Methodology, Resources, Supervision, Writing – review & editing. All authors reviewed the article, contributed to the discussion of results, approved the final version for submission and publication and take responsibility for the integrity of its findings.

This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

The data that support the findings of this study are available from the corresponding author, Ashok R, upon reasonable request.

The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of any affiliated agency of the authors, or that of the publisher. The authors are responsible for this article’s results, findings, and content.

References