2. LITERATURE REVIEW

2.1. Theoretical Framework

The empirical marketing model provides the foundation of this study, which considers the association of SMA and CPI across the Saudi retail e-commerce industry and applies the Theory of Planned Behaviour (TPB) as a theoretical framework of the current research. The TPB is a conceptual framework that can offer a solid conceptual familiarity with the way behavioural intentions grow out of information-related evaluations, social influence, or perceived ability to act of individuals, as recommended by (KV et al., 2021; Al Halbusi et al., 2023; and Rusidah, S. & Hairudinor., 2023). Instead of serving as a rigorously tested explanatory framework, the TPB is used to place the SMA. The present research examines the predictive association amid SMA and CPI in the e-commerce context of Saudi Arabia. Regarding consumer intentions in the digital commerce domain, the TPB is uncovered in numerous previous researches on digital commerce, even in those where the constructs of this theory were not explicitly included in the empirical model (Azad        et al., 2023). As in the larger body of work, TPB only appears in the theoretical background of TPB-related studies on behavioural intention. The empirical model of this study only considers the association amongst SMA, consumer trust, and CPI.

This study builds on (Khaleeli’s, 2020) research on the association amongst SMA and CPI by empirically validating the relationship in the fast-changing e-commerce landscape of Saudi Arabia. Previous research, such as (Ingriana, 2025), has explored the same kind of relationship in various national and sectoral settings, but little evidence exists from the Saudi retail e-commerce market, which is defined by high levels of digital adoption, growth of online retail, and high engagement with social media. Furthermore, consumer trust was explored as a boundary condition that can affect this association between the constructs. The proposed empirical model incorporates these components, providing context-specific insights and cultivating the comprehension of consumer behaviour and effectiveness of digital marketing in the case of contemporary e-commerce of Saudi Arabia.

The impact of SMA varies among consumers, and trust of consumers is the theoretical foundation for this. A higher level of trust in e-commerce platforms is linked to positive attitudes towards advertising claims, less handling of promotional messages, and less online buying uncertainty. In this context, the impact of persuasive social media advertising is likely to be more easily converted to buying intent. Under these circumstances, familiarity with convincing social media advertising is anticipated to translate more readily into purchase intention. In contrast, customers with lower levels of trust are more likely to question the trustworthiness of advertising content, assess advertising claims more vigilantly, and remain cynical towards online transactions. Thus, there is a theoretical basis for studying consumer trust as a moderator amongst SMA and CPI, as the same advertising messages can elicit different behavioural responses from consumers with varying levels of trust.

2.2. Hypotheses Development

The available literature identifies Social Media Advertising (SMA) as an organised persuasive tool that conceptually conforms to the Theory of Planned Behaviour (TPB) through well-stipulated psychological pathways but not arbitrary associations. TBP also tends to conceptualise purchase intention as associated with evaluative and social factors, which gives an overall background to the marketing-intention association, as indicated by the study of (Akayleh, 2021; Ingriana, 2025) also. In this context, SMA has been identified in previous digital research to have augmented CPI because of its interactivity, informational, and emotional content. Based on this literature, the current research proposes an empirical investigation of the association between SMA and CPI without testing the underlying behavioural belief structures. (Yeo et al., 2020) demonstrate that interactivity, richness of information, vividness, and brand image are important determinants of online purchase intention in Malaysia, which means that there is a formation of attitude, which is backed by social validation clues involved in SMA. Similarly, (KV et al., 2021) observed that creative implementation, emotional appeal, design that draws attention, and celebrity approval reinforce purchase intention in terms of the credibility of the message and social approval. These results empirically support the available evidence of TPB-congruent effects between SMA and the processes of forming a purchase intention.

Although such general convergence exists, contextual inconsistencies have also been found in the empirical evidence. In a study of consumers in the UAE, (Khaleeli, 2020) concluded that sales promotions on social media have a substantial relationship with CPI, but SMA does not. This discrepancy indicates that the usefulness of SMA might be contingent on contextual influences such as the market situation and consumer scepticism. Promotional incentives can be more important than persuasive advertising messages in a setting where consumers feel there is greater transactional risk or where consumers have lower control.

Influencer marketing studies reveal the relationship between the quality of information to be provided, entertainment quality, and perceived authority of influencers with increasing CPI in e-commerce settings. For example, (Saima & Khan, 2020) demonstrated that the credible and entertaining content of an influencer is positively associated with CPI. Such results provide a contextual understanding of how the content characteristics or features of SMA can influence the behaviour of potential consumers in an online environment without empirically involving behavioural mechanisms.

However, the methodological limitations of these studies restrict the ability to integrate theories and transfer the results to the context. For instance, the studies relied on self-reported cross-sectional surveys, which makes them more susceptible to common method bias, as is the case in (KV         et al., 2021). The sample size is usually inferior or it can be said that constrained geographically, in the case of 76 respondents in the study of (Saima & Khan, 2020), which minimises statistical power and generalisability. Furthermore, the mainstream of evidence is in Malaysian, Indian, or UAE settings, which limits the generalisability to the progressing ecosystem of e-commerce or online retail in Saudi Arabia. Therefore, existing evidence confirms SMA intention relationships but demands a Saudi-centred synthesis with the inclusion of trust in the e-commerce setting. Based on these emerging arguments from the review of existing studies, the subsequent claim (H1) is proposed:

H1: Social media advertising is significantly and positively allied with consumer purchase intention in the Saudi Arabian e-commerce industry.

As commonly understood, consumer trust is an aspect that determines online purchase behaviour, especially in digital contexts characterised by uncertainty and perceived risk. Contemporary literature on behavioural intention such as (Al Kurdi et al., 2024; Ki et al., 2023), including the TPB acknowledges the presence of trust, a factor regularly linked with consumers’ responses to marketing communications and decision-making regarding transactions. These perspectives provide a conceptual underpinning for the observed moderating effect in the present study. Experiential studies have shown that trust improves consumers’ confidence with online platforms, thus increasing their willingness to transact.

In the social context of marketing, the notion of trust is also examined and analysed in various theoretical contexts and has produced inconclusive but insightful results. As (Manzoor et al., 2020) depicted, SMA has a constructive association with the purchase intention of Pakistani consumers, and trust acts as a moderator by establishing the trustworthiness of the SMA. According to their findings, trust increases the likelihood that consumers will shape their positive behaviours towards trustworthy brands and make purchase intentions.  Nonetheless, the small size and geographically constrained sample of the study restricts the implementation and practicality of the results and findings to other emerging marketplaces and industries.

Furthermore, (Rehman et al., 2019) provide evidence suggesting that consumer trust plays a role in online CPI and moderates the relationship between SMA and CPI. Their results indicate that trust predisposes consumers to interpret social cues and assess brand claims in SMA. However, the use of convenience sampling and a cross-sectional design creates doubt regarding sampling bias and the ability to make a rationale and evidence-based conclusion. More context-specific and methodologically sound studies are needed. (Coutinho et al., 2023; and Ebrahimi et al., 2023) also claimed that conceptual influence on purchase intentions can be produced by consumer beliefs, which can affect purchase intentions; however, SMA catalyse this association.

The moderating influence of trust is also justified by the results of related industries. Research on digital marketing in the banking industry (Enehasse & Saglam, 2020; Otopah et al., 2024) validates that trust moderates the association digital marketing with engagement of consumers, which is eventually and related with the CPI. While earlier studies have revealed the applicability of behavioural frameworks, the results are highly industry-based and are not necessarily applicable in retail e-commerce, where the frequency of purchases, attitude to risk, and interaction with the platform are different. Trust has also been mentioned as a significant moderating factor in digital purchase decisions in previous studies. This clarifies the significance of the current research which emphasises trust as a moderator in the Saudi e-commerce environment. This elucidates the significance of the current study which stresses trust as a moderator in the e-commerce environment of Saudi Arabia.

Consumer trust provides a credible mechanism by which the efficacy of social media advertising varies among customers. According to (Manzoor et al., 2020), advertising messages are more probable to be professed as credible a reliable and considered at higher trust and credibility levels on e-commerce platforms. (Coutinho et al., 2023) also specified that a optimistic attitude improves receptivity to promotional messages and enhances the consequence of advertising exposure on CPI. On the other hand, consumers who are less trusting might be more critical about the claims made in advertising, doubt the accuracy of promotional information, and be wary of online transactions even after being exposed to advertising, as suggested by (Otopah et al., 2024). Consequently, the same advertising message could induce different consumer behaviours depending on the consumer’s level of trust. Therefore, its influence on consumer purchase intentions in e-commerce contexts could increase or decrease depending on consumer trust. 

Consequently, based on these arguments, H2 of the current study is developed:

H2: Consumer trust significantly moderates the association amid SMA and CPI in the case of e-commerce sector of Saudi Arabia.

2.3. Research Gaps

Notwithstanding the mounting body of literature evaluating the relationship between SMA and CPI, various gaps exist in context and methods. First, most studies, such as those by (Saima and Khan, 2020; and Yeo et al., 2020), are conducted in countries such as Malaysia, India, and the UAE, which creates a major contextual gap when it comes to Saudi Arabia and its e-commerce market, which has peculiar cultural, technological, and consumer trust relationships. The contribution of SMA in determining CPI in the retail e-commerce sector of Saudi Arabia, especially from the perspective of consumer behaviour trends and levels of trust, has not been successful.

Second, in terms of methodological gaps, most previous studies use convenience or purposive sampling (Jabeen et al., 2024; Manzoor et al., 2020) which restricts the generalisation of the results and findings. The sample sizes are frequently small in studies such as (Khaleeli, 2020; and Saima & Khan, 2020), and they are mainly cross-sectional, limiting the ability to make statistical inferences. In addition, moderating variables, including consumer trust, have not been well integrated into the analysis of the efficiency of SMA in purchase intention. Filling these gaps by undertaking an empirical study in Saudi Arabia through a contextually appropriate non-probability sampling approach, a bigger sample, and utilisation of trust as a moderator offers and in-depth theoretical as well as practical input towards current literature on digital marketing and e-commerce. The emerging arguments and facts from the above review of literature, the identified research gaps and purpose of this research, Fig. (1) provides conceptual framework of the study.