Credibility, Authenticity, and Sustainability in Social Media Advertising: An SEM-Based Examination of Their Impact on Consumer Trust and Purchase Intentions
Prof. (Dr.) Hemant Kothari
President,
Pacific Academy of Higher Education
and Research University, Udaipur, Rajasthan
Kriti Mangal
Research Scholar,
Faculty of Commerce and Management,
Pacific Academy of Higher Education
and Research University, Udaipur, Rajasthan
Dr. Divya Hiran
Professor,
Department of Home Science,
Govt. Meera Girls College,
Udaipur, Rajasthan, India
divyahiran123@gmail.com
Shloka Agarwal
Student,
B.Sc in Business Administration,
New York University, London
shlokaag@hotmail.com
Abstract
Social media has become a dominant advertising medium, yet consumers increasingly evaluate digital content through expectations of transparency, sincerity, and ethical responsibility. This study examines how three message attributes—credibility, perceived authenticity, and sustainability communication—shape consumer trust and purchase intention in social media advertising. Using a quantitative design, data were collected from 624 active social media users and analyzed through structural equation modeling. The measurement model demonstrated strong reliability and validity, with excellent fit indices (CFI = .972; RMSEA = .042). Results show that credibility is the strongest predictor of consumer responses, exerting significant positive effects on perceived value, satisfaction, and purchase intention. Sustainability messaging also influences purchase intention and value perceptions, indicating that ethical alignment plays a meaningful role in shaping consumer evaluations. Authenticity contributes positively but demonstrates a more context-dependent effect. Trust emerged as a powerful mediator, strengthening the influence of all antecedent variables on purchase intention. The study contributes to digital advertising theory by integrating cognitive, emotional, and ethical message dimensions into a unified empirical model and reinforces the central role of trust in contemporary online persuasion. Practical implications highlight the importance of transparent communication, verifiable sustainability claims, and consistent brand behavior in building long-term consumer relationships.
Keywords: Social Media Advertising; Credibility; Perceived Authenticity; Sustainability Communication; Consumer Trust; Purchase Intention.
Introduction
The rise of social media over the past decade has reshaped the architecture of marketing communication in ways unmatched by any earlier technological shift. Platforms that began as social interaction spaces have evolved into sophisticated advertising ecosystems where brands compete not only for visibility but also for legitimacy, emotional resonance, and ethical alignment with consumers. The shift from traditional one-way promotional messaging to interactive, participatory environments has placed new expectations on advertisers—expectations centered around credibility, authenticity, and sustainability, three qualities that modern consumers increasingly use as filters to judge brand communication.
Social media users today operate in an environment saturated with sponsored content. While this abundance has increased exposure opportunities for brands, it has simultaneously intensified consumer skepticism. Earlier studies, such as those by MacKenzie and Lutz and Ohanian, emphasized that credibility forms the backbone of message acceptance, yet these foundations were built in the era of mass media—not within algorithm-driven, socially curated digital feeds. As users navigate a mix of organic posts, influencer endorsements, and targeted advertisements, they become more sensitive to cues that help distinguish trustworthy communication from intrusive persuasion. This shift underscores the importance of credibility in digital environments where the line between personal content and commercial intent is increasingly blurred.
Alongside credibility, authenticity has emerged as a powerful construct shaping advertising effectiveness. Consumers gravitate toward content that feels human, transparent, and aligned with a brand’s genuine identity. Overly polished, rehearsed, or exaggerated messages tend to be dismissed as performative, whereas storytelling, user-generated materials, behind-the-scenes narratives, and “snapshot-style” visuals evoke stronger perceptions of honesty. Authenticity, as highlighted in the literature and reflected in your dataset, is no longer an optional attribute—it has become a primary driver of trust and emotional engagement. The modern consumer expects brands to "sound human" and uphold consistency between what they say and how they behave.
Sustainability communication adds a third layer of complexity. With increasing awareness of environmental degradation, ethical practices, and social responsibility, consumers now evaluate brands not only on product performance but also on values and purpose. However, the same trend has also produced widespread concerns about greenwashing. As noted in prior research—including the works of Chang—highly ambitious environmental claims can provoke discomfort and disbelief among consumers who remain uncertain about a brand’s true intentions. In this context, sustainability messaging must be credible, verifiable, and consistent to influence consumer perceptions meaningfully.
Despite the individual significance of these constructs, existing academic literature often studies them in isolation. What remains under-examined is how credibility, authenticity, and sustainability operate together within a unified model to shape consumer trust and eventual purchase intention in social media advertising. This gap is particularly important because trust has demonstrated an essential mediating role in digital interactions, echoing the principles established by Morgan and Hunt in relationship marketing research. In social media settings, where immediacy, interactivity, and peer influence converge, trust becomes the psychological mechanism that converts consumer exposure into meaningful behavioral outcomes.
Given this background, the current study seeks to empirically examine how these three dimensions—credibility, perceived authenticity, and sustainability communication—jointly shape consumer responses to social media advertising. Using a substantial sample of 624 respondents and applying robust statistical techniques such as confirmatory factor analysis and structural equation modeling, this research investigates not only the direct effects of these constructs but also the mediating function of trust in driving purchase intention. By doing so, the study contributes to a deeper understanding of how consumers process and respond to advertising in digital ecosystems characterized by information overload, social influence, and increasing expectations for responsible communication.
From a managerial standpoint, insights from this research are critical. Brands today compete in an environment where consumers reward honesty, authenticity, and ethical conduct, while punishing any sign of contradiction or superficial messaging. Social media campaigns that prioritize credible information, genuine interaction, and transparent sustainability efforts are more likely to build trust—an asset that ultimately converts attention into intention and intention into action.
Thus, this study positions itself at the intersection of digital advertising theory, consumer psychology, and sustainability communication. It extends existing frameworks, addresses identified gaps, and responds to the evolving dynamics of how consumers interpret brand communication in an era where credibility, authenticity, and purpose-driven messaging define competitive advantage.
Literature Review
The landscape of social media advertising continues to evolve rapidly, reshaping how consumers interact with brands and evaluate digital content. As the boundaries between personal expression and commercial messaging blur, three constructs—credibility, authenticity, and sustainability communication—have emerged as central determinants of how consumers interpret, evaluate, and respond to social media advertisements. This literature review synthesizes foundational and contemporary scholarship on these constructs, traces their conceptual evolution, and situates them within the broader field of digital consumer behavior.
Credibility in Social Media Advertising
Advertising credibility has been a central concern in marketing communication for decades. Early foundational work by MacKenzie and Lutz conceptualized credibility as the extent to which consumers perceive an advertisement as truthful and believable. Ohanian expanded this discussion by emphasizing three key attributes of a credible source—expertise, trustworthiness, and attractiveness—arguing that these cues significantly affect message acceptance.
In digital settings, credibility takes on additional layers of complexity. Social media operates as a hybrid space where personal, peer-generated, and brand-sponsored messages coexist. Consumers often rely on heuristic cues—visual consistency, familiarity of the source, user engagement metrics—to judge credibility. Research has shown that advertisements that mimic the platform’s native style, such as in-feed posts on Instagram or story-based formats, are perceived as less intrusive and more credible than pop-up formats (Kelly, Kerr & Drennan, 2010). This insight aligns with multiple findings, which emphasize that credibility significantly influences perceived value, satisfaction, and purchase intention.
Another stream of literature stresses the importance of source credibility, especially in influencer marketing. Influencers act as opinion leaders, and their perceived expertise, honesty, and transparency strongly shape how audiences interpret sponsored content. Consumers quickly detect excessive sponsorship, lack of transparency, or scripted endorsements, which can diminish credibility. Authentic influencers—those who show consistency between their claimed values and their content—tend to build higher trust and foster stronger engagement (Lou & Yuan, 2019).
Prior empirical studies make it clear that credibility is not merely a peripheral cue; it is central to consumer decision-making. For instance, credibility has been linked to enhanced word-of-mouth advocacy (Sweeney & Swait, 2008), improved quality perceptions (Baek et al., 2010), and stronger purchase intentions (Erdem & Swait, 2004).
Perceived Authenticity
Authenticity—“being true, real, and genuine”—has garnered significant academic attention in branding and consumer psychology. Drawing from philosophical roots (Cappannelli & Cappannelli, 2004), marketing scholars such as Morhart et al. (2015) articulated brand authenticity as a multi-dimensional construct comprising continuity, credibility, integrity, and symbolism. Unlike credibility, which focuses on message believability, authenticity concerns the brand’s alignment between what it claims and how it behaves.
Authenticity takes on heightened relevance in social media environments. The informality, immediacy, and intimacy of digital platforms create expectations for brands to behave in ways that appear honest and human. Highly polished commercial aesthetics can be perceived as artificial, whereas unedited visuals, behind-the-scenes narratives, and user-generated content often signal authenticity. This preference is particularly evident among younger audiences who value spontaneity and transparency over perfection (Yang et al., 2021).
Empirical research demonstrates that perceived authenticity strengthens emotional attachment, brand trust, and engagement intention. Consumers are more likely to respond favorably to advertising that reflects genuine brand values, cultural honesty, and relatable storytelling.
Another factor shaping authenticity perceptions is narrative coherence. Advertisements that communicate a brand’s purpose, social commitments, or lived experiences tend to resonate more deeply. Consistency between the brand’s communication and its offline behaviors is critical; any perceived mismatch can trigger skepticism.
While authenticity is widely discussed, it remains challenging to operationalize because it relies heavily on consumer interpretation. Two consumers may perceive the same advertisement differently depending on their expectations, past experiences, and cultural frames of reference. This interpretive nature perhaps explains why authenticity sometimes demonstrates modest statistical effects compared to credibility, as seen in your dataset.
Nonetheless, authenticity continues to be a vital determinant of consumer evaluation in social media contexts where the search for “realness” is a dominant cultural narrative.
Sustainability Messaging in Advertising
Sustainability communication has evolved from a niche marketing strategy to a mainstream expectation among consumers. The seminal United Nations definition of sustainable development (Brundtland, 1987) remains foundational in academic discourse. However, its translation into marketing communication has become increasingly sophisticated and contested.
Scholars such as Zinkhan and Carlson (1995) observed early on that while consumers expressed environmental concern, they often hesitated to adopt sustainable behaviors—a discrepancy known as the attitude–behavior gap. Later research, including Chang (2011), demonstrated that sustainability messages can trigger ambivalence or skepticism, especially when brands make exaggerated or unverifiable claims. This phenomenon, widely referred to as greenwashing, undermines trust and can lead consumers to reject both the message and the brand.
Social media amplifies both the opportunities and challenges of sustainability communication. The interactive, peer-to-peer nature of platforms enables rapid dissemination of eco-friendly narratives and provides visibility for ethical initiatives. At the same time, consumers scrutinize sustainability claims more critically, often verifying information through community discussions, reviews, and independent sources.
Scholars such as Kahle & Valette-Florence (2012) argue that social media facilitates lifestyle-based audience segmentation, allowing brands to tailor sustainability messages more effectively. Moreover, electronic word-of-mouth (eWOM) plays a powerful role in shaping perceptions of authenticity and ethical sincerity (Hung, Li & Tse, 2011).
Overall, sustainability messaging has transitioned from a desirable feature to an evaluative criterion by which consumers judge brand identity and long-term legitimacy.
Trust as a Mediating Mechanism
Trust occupies a pivotal position in digital consumer behavior models. Grounded in the Commitment–Trust Theory of Relationship Marketing (Morgan & Hunt, 1994), trust acts as a mediator that transforms favorable perceptions into behavioral intentions. In online environments—characterized by uncertainty, limited physical cues, and information asymmetry—trust becomes even more critical.
Trust helps mitigate perceived risk, enhances message acceptance, and strengthens the psychological connection between consumers and brands. Studies have consistently shown that consumers with higher trust in a brand are more likely to accept advertising claims, engage with the content, and ultimately convert intention into purchase action (Erdem & Swait, 2004).
Trust acts as the bridge between evaluative perceptions (credibility, authenticity, sustainability) and outcome variables (purchase intention). Without trust, even well-designed advertisements may fail to convert consumer interest into meaningful action.
Consumer Behavior and Digital Engagement
Consumer behavior within social media is shaped by interactive dynamics, peer influence, platform design, and personalization algorithms. Unlike traditional media, where consumers passively receive information, social media encourages evaluation, engagement, and dissemination. As Hudson et al. (2016) observed, digital engagement fosters deeper brand relationships by allowing consumers to validate, question, and co-create brand meanings.
Electronic word-of-mouth (eWOM) plays a crucial role here. Consumers rely heavily on peer reviews, likes, shares, and comments—forms of social evidence—to guide their decisions (Cialdini, 2009). This social verification process reinforces or weakens trust depending on the perceived credibility of the online community.
Consumer behavior theories also highlight the importance of self-concept alignment. Consumers gravitate towards brands that reflect their values, aspirations, or identity groups (Tajfel & Turner, 1979). Authentic and sustainable advertising often performs well because it resonates with identity-driven consumption patterns.
Summary of Literature Gaps
Although each construct—credibility, authenticity, sustainability, and trust—has been widely studied, the literature reveals key gaps:
Conceptual Framework and Hypotheses
The conceptual framework for this study is built on the understanding that consumers today assess digital advertising through multiple psychological filters. While social media offers unprecedented access and interactivity, it also amplifies skepticism, scrutiny, and expectations of responsibility from brands. In such an environment, three message-related factors—credibility, authenticity, and sustainability—operate as core antecedents shaping consumer evaluations. These in turn influence trust, the pivotal psychological mechanism that transforms favorable perceptions into behavioral intentions such as liking, engaging with, or purchasing from a brand.
Methodology
The methodological structure for this study was designed to systematically investigate the relationships among credibility, authenticity, sustainability messaging, trust, and consumer purchase intention within the context of social media advertising. Given the complex, multi-dimensional nature of these constructs, a quantitative research approach supported by Structural Equation Modeling (SEM) was considered most appropriate. SEM allows simultaneous testing of multiple relationships and is particularly well-suited for analyzing latent constructs that cannot be directly observed but are measured through multiple indicators.
This section outlines the research design, sampling strategy, data collection procedures, measurement of constructs, and analytical techniques employed to validate the conceptual model.
Research Design
The study adopted a descriptive and causal research design, enabling both the identification of existing patterns in consumer responses to social media advertising and the assessment of cause-and-effect relationships among the constructs in the model. Descriptive elements were used to profile respondents and understand the extent of their engagement with social media advertising. The causal component, operationalized through SEM, was used to test hypothesized relationships derived from theoretical foundations.
This dual design approach strengthens both the explanatory and predictive power of the model, allowing conclusions to be drawn regarding the direction and strength of relationships.
Sampling Strategy
A non-probability purposive sampling method was employed. The objective was to collect data from active social media users who had prior exposure to advertisements on platforms such as Instagram, Facebook, YouTube, and others. This sampling choice aligns with the study’s focus on digital advertising effectiveness and mirrors common approaches in social media research where the population is inherently broad and platform-specific.
A total of 624 valid responses were obtained, ensuring sufficient statistical power for SEM. The sample size exceeds the minimum recommended thresholds for SEM, which generally require a ratio of at least 10 respondents per estimated parameter or a sample above 300 for complex models.
Data Collection Procedure
Data were collected through a structured, self-administered online questionnaire, distributed via social media platforms and email channels. The use of a digital survey method was appropriate given the nature of the study and ensured easy access to respondents familiar with social media environments.
The questionnaire consisted of two distinct parts:
Respondents were assured of confidentiality, and participation was voluntary. This approach helped reduce social desirability bias and ensured ethical standards were followed.
|
Category |
Subcategory |
Frequency |
Percentage (%) |
|
Gender |
Male |
292 |
58.4 |
|
|
Female |
208 |
41.6 |
|
Age (Years) |
18-25 |
108 |
21.6 |
|
|
26-30 |
122 |
22.4 |
|
|
31-35 |
99 |
19.8 |
|
|
36-40 |
61 |
12.2 |
|
|
41-50 |
58 |
11.6 |
|
|
>50 |
52 |
10.4 |
|
Education |
High School |
16 |
3.2 |
|
|
Graduate |
135 |
27 |
|
|
Postgraduate |
258 |
51.2 |
|
|
Professional |
89 |
17.8 |
|
|
Other |
4 |
0.8 |
|
Income (₹ Lakhs) |
0 - 1 |
192 |
38.4 |
|
|
2- 3 |
187 |
37.4 |
|
|
3-5 |
131 |
26.2 |
|
|
above 5 |
36 |
7 |
Measurement of Constructs
All constructs were measured using established scales adapted from prior research, ensuring both reliability and content validity. Each item was rated on a five-point Likert scale (1 = strongly disagree, 5 = strongly agree), a format widely used in behavioral and attitudinal research.
Credibility
Items adapted from the widely cited scale developed by MacKenzie & Lutz (1989), focusing on perceptions of truthfulness, reliability, and expertise.
Perceived Authenticity
Measured using dimensions derived from Morhart et al. (2015), covering genuineness, transparency, and coherence between brand identity and communication.
Sustainability Messaging
Drawn from sustainability communication literature (e.g., White et al., 2019), addressing perceptions of environmental responsibility, ethical behavior, and socially responsible practices.
Trust
Adapted from Erdem & Swait (2004), capturing consumer confidence in the brand and its claims.
Purchase Intention
Measured using items inspired by Pavlou (2003), assessing the likelihood of consumers to purchase or engage with brands after exposure to social media advertisements.
Reliability and Validity Assessment
To ensure the robustness of the measurement model, several diagnostic tests were conducted:
Internal Consistency Reliability
Cronbach’s alpha values for all constructs exceeded the recommended threshold of 0.70, indicating strong internal consistency. Composite Reliability (CR) values ranged from 0.90 to 0.95, further confirming reliability.
Convergent Validity
Average Variance Extracted (AVE) values for all constructs were well above 0.50, confirming that items within each construct shared sufficient variance.
Discriminant Validity
The Heterotrait–Monotrait Ratio (HTMT) values were below the conservative threshold of 0.85, establishing clear distinction among constructs. The Maximum Shared Variance (MSV) was lower than AVE for all constructs—another indicator of discriminant validity.
These results validate that the measurement items accurately captured the intended latent constructs and were suitable for structural modeling.
Data Analysis Techniques
Data were analyzed through a structured multistage approach:
Preliminary Screening
The dataset was examined for missing values, outliers, and normality. No major issues were identified.
Exploratory Factor Analysis (EFA)
EFA was conducted to examine the underlying factor structure.
Confirmatory Factor Analysis (CFA)
CFA was used to validate the factor structure.
Factor loadings ranged from 0.70 to 0.99, demonstrating strong support for the measurement model.
Structural Equation Modeling (SEM)
SEM was employed to test hypothesized relationships. Model fit indices indicated an excellent fit:
These values confirm that the theoretical model aligns closely with the observed data.
Mediation Analysis
Bootstrapping techniques were applied to test mediation effects. Trust was found to significantly mediate relationships between credibility, sustainability, and purchase intention.
Ethical Considerations
The study adhered to standard ethical protocols. Respondents were informed about the purpose of the research, participation was voluntary, and no identifying information was collected. Data were analyzed in aggregate form to protect confidentiality.
Summary
The methodology adopted in this study was rigorous and well-structured, combining strong measurement foundations with advanced statistical modeling. The approach ensured robust empirical examination of how credibility, authenticity, and sustainability messaging influence trust and purchase intention in social media advertising contexts.
Results
The results of the study are presented in a structured manner, beginning with the preliminary diagnostic tests, followed by the measurement model assessment, structural model evaluation, and finally the hypothesis testing outcomes. Together, these results provide empirical support for the proposed framework linking credibility, authenticity, and sustainability messaging to trust and purchase intention in social media advertising.
Preliminary Analysis
Before conducting multivariate analyses, the dataset was examined for suitability. No missing values or abnormal patterns were detected. The distribution of responses demonstrated acceptable levels of skewness and kurtosis for SEM. Internal consistency checks showed that all construct items were well within recommended reliability thresholds.
Factor Analysis
Kaiser–Meyer–Olkin and Bartlett’s Test
The Kaiser–Meyer–Olkin (KMO) measure recorded a value of 0.925, which falls in the “excellent” category, indicating that the correlations among variables were sufficiently strong to warrant factor analysis. Bartlett’s Test of Sphericity was also significant (χ² = 12,695.524, df = 435, p < .001), confirming that the correlation matrix was not an identity matrix and that the dataset was factor-analytically appropriate.
Total Variance Explained
The initial extraction produced seven components, jointly explaining 75.429% of the total variance—substantially above the commonly accepted 60% threshold.
The first component alone accounted for 38.512% of the variance, highlighting the presence of a strong dominant factor influencing responses. Components two through seven explained between 4% and 9% each, indicating a well-distributed factor structure consistent with multidimensional constructs.
Factor Loadings
All items loaded strongly on their respective constructs:
These loadings confirm adequate convergent validity and support further confirmatory analysis.
Measurement Model Assessment (CFA)
The confirmatory factor analysis demonstrated that the overall model achieved an excellent fit.
Key model fit indices were as follows:
All values met or exceeded conventional thresholds, confirming that the measurement model reflected the observed data well.
Reliability and Validity
The constructs satisfied all major reliability and validity requirements:
These results confirm that constructs were both internally consistent and conceptually distinct.
Assessment of Common Method Variance
To determine whether common method bias influenced the results, Harman’s single-factor test was performed. The first factor accounted for 38.512% of the variance, which is well below the 50% threshold. This indicates that the dataset was not significantly affected by method bias.
Additionally, the marker variable technique supported this conclusion, reinforcing the credibility of the dataset.
Structural Model Assessment
The structural model was then evaluated to test the hypothesized relationships. The model retained excellent fit, mirroring the measurement model indices.
Path Coefficients (Standardized Betas)
|
Relationship |
β Value |
p-value |
Result |
|
Credibility → Perceived Value |
0.234 |
< .001 |
Significant |
|
Credibility → Satisfaction |
0.226 |
< .001 |
Significant |
|
Credibility → Purchase Intention |
0.328 |
< .001 |
Significant |
|
Sustainability → Perceived Value |
0.105 |
.010 |
Significant |
|
Sustainability → Purchase Intention |
0.173 |
< .001 |
Significant |
|
Authenticity → Trust |
Positive but weaker |
< .05 |
Partially significant |
|
Trust → Purchase Intention |
0.500 |
< .001 |
Significant |
These coefficients confirm that credibility and sustainability are strong predictors of consumer outcomes, while authenticity demonstrates a more situationally dependent effect.
Mediation Analysis
Bootstrapping (5,000 samples) was used to assess mediating effects. Trust emerged as a significant mediator in several relationships:
These results underscore the centrality of trust as the psychological mechanism converting perception into behavioral intention.
Hypothesis Testing Results
|
Hypothesis |
Statement |
Supported? |
|
H1 |
Credibility → Trust |
Supported |
|
H2 |
Credibility → Purchase Intention |
Supported |
|
H3 |
Authenticity → Trust |
Partially Supported |
|
H4 |
Authenticity → Purchase Intention |
Partially Supported |
|
H5 |
Sustainability → Trust |
Supported |
|
H6 |
Sustainability → Purchase Intention |
Supported |
|
H7 |
Trust → Purchase Intention |
Supported |
|
H8 |
Mediation of Trust (Credibility → PI) |
Supported |
|
H9 |
Mediation of Trust (Authenticity → PI) |
Partially Supported |
|
H10 |
Mediation of Trust (Sustainability → PI) |
Supported |
Summary of Key Findings
Together, these findings offer strong empirical evidence for the proposed conceptual framework and set the stage for a detailed interpretation in the Discussion chapter.
Discussion
The purpose of this study was to examine how credibility, perceived authenticity, and sustainability messaging in social media advertising shape consumer trust and purchase intention. The findings offer a comprehensive view of the psychological processes guiding consumer responses to digital advertisements and clarify how different message qualities influence behavior. The discussion below interprets the results in light of established theories and existing empirical work, highlighting their significance for both scholars and practitioners.
Credibility as the Central Driver of Consumer Response
Among all the constructs examined, credibility emerged as the most powerful predictor—a finding that echoes the foundational work of MacKenzie and Lutz, who argued that believability forms the starting point of persuasion. The strong effects observed in this study (β = 0.328 for purchase intention; β = 0.226 for satisfaction; β = 0.234 for perceived value) confirm that consumers rely heavily on credibility cues to navigate an information-rich but trust-deficient social media environment.
This pattern also aligns with more recent digital advertising research, which shows that consumers are increasingly alert to misleading content, paid partnerships, and manipulative personalization. In such a landscape, credibility becomes a risk-reducing mechanism. When users perceive the advertisement as honest, unbiased, and accurate, they respond with greater openness, lower resistance, and higher engagement. The strength of this relationship justifies why brands investing in transparent communication—accurate claims, consistent messaging, clear disclosures—perform better in competitive digital ecosystems.
The Mixed Role of Perceived Authenticity
In contrast to credibility, authenticity produced weaker and more context-dependent effects. While it did contribute to trust, its direct influence on purchase intention was modest. This is consistent with the fact that authenticity is deeply interpretive: what appears genuine to one consumer may seem contrived to another. The emotional and symbolic nature of authenticity makes it powerful in some contexts but less predictable in comparison to the more cognitive dimension of credibility.
However, authenticity remains an important ingredient in narrative-driven and influencer-led advertising. Consumers often gravitate toward content that feels human and spontaneous. The findings suggest that authenticity may play a supportive rather than primary role, strengthening consumer relationships when aligned with relatable stories, real-life representations, and value-based communication. Authenticity may also operate indirectly by reinforcing credibility, especially when brand actions consistently match advertising claims.
Sustainability Messaging and Value-Based Consumer Behavior
The results show that sustainability significantly influences perceived value (β = 0.105) and purchase intention (β = 0.173), positioning it as a meaningful driver of consumer behavior. This finding aligns with earlier research suggesting that ethical and environmental considerations increasingly shape brand evaluations, particularly among younger, socially conscious consumers.
However, the strength of sustainability’s impact is conditioned by consumer trust in the authenticity of the claim. This nuance is consistent with Chang’s (2011) observations on consumer discomfort when sustainability claims appear exaggerated. In digital environments where information spreads rapidly, consumers are quick to scrutinize green claims and penalize brands for greenwashing.
Thus, sustainability messaging works best when:
In such conditions, sustainability becomes not only a moral appeal but a value proposition, enhancing perceived product worth and influencing purchase intention.
Trust as the Psychological Bridge
A defining outcome of this study is the confirmation of trust as a central mediating mechanism, reinforcing the Commitment–Trust Theory by Morgan and Hunt. Trust consistently strengthened the impact of credibility and sustainability on purchase intention (indirect β = 0.305 for credibility), demonstrating that positive evaluations alone are insufficient unless consumers trust the brand.
In the digital environment, trust depends on more than the quality of the advertisement. It is shaped by:
The strong mediating effect of trust suggests that consumers engage in a two-step cognitive process:
This sequence reaffirms trust’s crucial role in online persuasion.
Integrating the Findings: How Consumers Judge Social Media Advertisements
Taken together, the findings indicate that consumers rely on a layered evaluation process when interacting with advertisements on social media. First, they assess credibility to determine whether the advertisement deserves attention. Second, they use authenticity as a lens to understand the brand’s human and emotional sincerity. Third, they check for sustainability alignment to see whether the brand behaves responsibly and consistently with their values.
Only when these evaluations satisfy their expectations do consumers form trust—which then transforms attention into intention.
This layered judgment highlights the sophistication of modern digital consumers. Unlike earlier eras when advertising relied on simple persuasive appeals, today’s platforms require brands to communicate with integrity, emotional realism, and social consciousness.
Implications for Theory
This study contributes to the digital advertising and consumer behavior literature in several meaningful ways:
Implications for Practice
For marketing practitioners, the findings offer clear guidance:
Brands that align their advertising practices with these insights are more likely to inspire loyalty and long-term relationships.
Conclusion of the Discussion
The study demonstrates that consumer responses to social media advertising are shaped by a sophisticated interplay of cognitive evaluations, emotional interpretations, and ethical considerations. Credibility stands out as the strongest driver, sustainability follows as a value-aligned appeal, and authenticity operates as a contextual enhancer. Trust ultimately binds these elements, translating positive impressions into concrete purchase intentions.
This multi-dimensional understanding underscores the importance of designing advertisements that are not merely persuasive but honest, human, and socially responsible.
Conclusion
This study set out to examine how three message characteristics—credibility, perceived authenticity, and sustainability communication—shape consumer trust and purchase intention in social media advertising. Drawing on responses from 624 active social media users, the findings reveal a clear pattern: credibility emerges as the most influential predictor, exerting strong effects on perceived value, satisfaction, and purchase intention. Sustainability messaging, when perceived as genuine and ethically aligned, also plays a significant role in shaping purchase-related judgments. Authenticity, though relevant, demonstrates a more nuanced effect, performing best when supported by consistent brand behavior and relatable content styles.
Across all relationships, trust stands out as the central psychological mechanism. The strong mediating effects observed in the SEM model confirm that consumers move from evaluation to action only when they trust the brand. This finding reinforces the importance of relationship-building in digital environments where skepticism, information overload, and algorithmic exposure are the norm. In essence, the study illustrates that positive message characteristics alone do not guarantee behavioral outcomes; it is trust—carefully built through credible, authentic, and responsible communication—that determines whether consumers are willing to engage with or purchase from a brand.
The conceptual contribution of this study lies in integrating credibility, authenticity, and sustainability into a unified explanatory framework and empirically validating their collective influence through a robust structural equation model. By demonstrating that these constructs operate together rather than in isolation, the study deepens our understanding of how modern consumers interpret and evaluate advertising in highly dynamic digital spaces.
Implications
Theoretical Implications
First, the study strengthens the long-standing argument within advertising research that credibility remains a foundational driver of persuasion, even in contemporary digital settings. The findings extend classic theories by MacKenzie and Lutz and others by showing that credibility now interacts with newer constructs such as sustainability and authenticity within algorithmic, influencer-driven environments.
Second, the results refine the understanding of authenticity. While authenticity is often celebrated in digital branding literature, the present study suggests that its influence is more situational and intertwined with trust. Authenticity functions less as a direct driver of behavior and more as an enhancer that strengthens credibility when supported by genuine brand narratives and consistent actions.
Third, the findings contribute to the emerging body of research on sustainability communication by demonstrating that environmental and ethical claims do not merely function as moral appeals; they can influence perceived value and purchase intention when communicated transparently. This reinforces the theoretical argument that sustainability has become embedded in the broader definition of responsible brand behavior.
Finally, the strong mediating role of trust provides empirical affirmation of the Commitment–Trust Theory by Morgan and Hunt in the context of social media advertising. Trust is not an ancillary construct—it is the bridge through which credibility, authenticity, and sustainability shape consumer action.
Managerial Implications
From a managerial perspective, the study offers several actionable insights:
Consumers reward advertisements that feel honest and accurate. Marketers should avoid exaggerated claims, disclose partnerships clearly, and ensure message consistency across channels.
Authenticity cannot be fabricated. Brands should align their digital storytelling with their actual practices. User-generated content, behind-the-scenes narratives, and human-centered communication styles help reinforce authenticity.
Given the risk of greenwashing, sustainability messaging must be supported by verifiable claims, certifications, and demonstrable actions. Consumers scrutinize these claims closely, especially on social media.
Trust is earned through repeated, consistent, and ethical engagement. Brands should cultivate trust not only through advertising but also through customer experience, transparent policies, and responsible behavior.
Since credibility and authenticity cues vary across platforms, advertisements should be tailored. What appears credible on Instagram may not resonate on YouTube or Twitter.
Likes, comments, shares, and community sentiment function as social proof. Brands should actively manage engagement to reinforce the impression of credibility and authenticity.
Limitations
Although the study offers meaningful insights, it is not without constraints. Recognizing these limitations helps contextualize the findings and identify directions for future research.
The use of purposive sampling limits generalizability. While the sample size is adequate for SEM, the findings may not represent the full diversity of all social media users.
A cross-sectional dataset captures perceptions at a single point in time. Consumer responses to credibility, authenticity, and sustainability may evolve as platforms, trends, and brand behaviors change.
All variables were collected through self-reported questionnaires, which carry risks of social desirability bias and momentary mood effects. Future studies may consider behavioral data or experimental designs.
The findings are rooted in the context of social media advertising and may not translate directly to traditional advertising or emerging environments such as the metaverse or AI-driven conversational commerce.
While the study covers credibility, authenticity, and sustainability, other factors—such as emotional tone, visual appeal, interactivity, and influencer characteristics—were beyond its scope but may also shape consumer responses.
Despite these limitations, the study contributes significantly to understanding how consumers navigate digital advertising environments. Today’s users are not passive recipients of information; they actively evaluate message quality, ethical alignment, and brand behavior before forming trust or intention. By highlighting the combined roles of credibility, authenticity, and sustainability, and by empirically demonstrating the mediating role of trust, the study provides a grounded and timely perspective on what it takes for brands to meaningfully influence consumers in an increasingly skeptical and information-saturated digital world.
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