Influencer marketing effectiveness: giving competence, receiving credibility

ABSTRACT

Travel influencers often disclose personal details in their social media recommendations. However, previous research has not explained how such content impacts influencer evaluations. This study explores how intimate self-disclosure in influencer recommendations affects perceptions of credibility. An experimental study demonstrates that recommendations containing intimate (vs. without intimate) content diminish perceptions of the travel influencer’s credibility. The congruence between the influencer’s content and expertise plays a mediating role, with intimate content being perceived as incongruent with their expertise, thereby reducing credibility. Competence need fulfillment moderates this effect such that influencers’ credibility is enhanced through content-expertise congruence as participants feel more competent.

KEYWORDS:

• Travel influencer
• intimate self-disclosure
• congruence
• source credibility
• competence
• need fulfillment
• self-determination theory
• elaboration likelihood model
• influencer marketing effectiveness
• social media

Introduction

Travel marketers have increasingly recognized the potential of partnering with social media influencers for message amplification and precise targeting. Influencers, in turn, are attracted to the travel and tourism sector due to the appeal of travel incentives and the opportunity to align their personal brand with desirable travel and tourism brands (Schivinski et al., 2020). A recent study (American Express, 2023) revealed that 75% of consumers felt inspired by social media to travel to a specific destination. Furthermore, 46% of Gen Z and Millennials said their booking decisions are heavily influenced by travel content on Instagram (Influencer Marketing Hub, 2023). Indeed, past research in travel and tourism has shown that social media influencers significantly impact travel preferences (e.g. J. Ma & Li, 2022; Manthiou et al., 2024). Despite the notable prominence and practical importance of this phenomenon, there remains a noticeable dearth of research exploring the realm of travel and tourism influencer marketing, especially in terms of understanding how consumers perceive the communication of travel influencers and what factors contribute to the effectiveness of influencer messages.

One strategy within influencer marketing communication involves influencers sharing personal and intimate content on social media. This form of communication, in which individuals share private information about themselves, is known as self-disclosure (Altman & Taylor, 1973). Self-disclosure is inherent in genuine travel reviews and recommendations (K. Lee et al., 2022). This approach has been demonstrated to cultivate stronger relationships with their audience (e.g. Chen et al., 2021; Leite & Baptista, 2022b; E. S-T. Wang & Hu, 2021). However, the effectiveness of influencers’ persuasive communication also relies on perceptions that they are credible sources of advice to their followers (Djafarova & Rushworth, 2017; Hernández-Méndez & Baute-Díaz, 2023), raising concerns about using intimate content to enhance credibility. Considering that credible recommendations are crucial elements in influencer travel information (Choi et al., 2021; Manthiou et al., 2024), initiating a discourse on the effective use of intimacy in influencers’ social media content can be challenging.

While influencers’ self-disclosure can sometimes be detrimental to their positive evaluations (AlRabiah et al., 2022; Johnson et al., 2022; Leite et al., 2022), previous research indicates that self-disclosure can enhance perceptions of credibility through relationship-related factors such as parasocial interactions (e.g. Penttinen et al., 2022). This means that credibility can be bolstered through relationship-related factors (Baxter et al., 2022). The rationale is that self-disclosure can enhance relational ties between the discloser and those who receive the self-disclosure (Altman & Taylor, 1973). However, a notable concern arises from the reliance on influencers’ capacity to cultivate strong connections with their audience. Regrettably, not all influencers can maintain active reciprocity with their followers (Leite & Baptista, 2022b), making it difficult to establish relationships that resemble dyadic relationships. This suggests that the relationships between influencers and their audience do not always follow the typical progression of dyadic relationships, where individuals initially share superficial information and gradually reveal more in-depth details about themselves as the relationship develops (Altman & Taylor, 1973). In the influencer-follower interaction, more intimate information about the influencer can become easily accessible in early encounters with their audience. Based on this issue, it remains unclear how influencers’ intimate self-disclosure can enhance perceptions of credibility without relying entirely on their abilities to create relational bonds with their followers.

Despite some previous studies on self-disclosure in travel settings (e.g. Cai et al., 2024; Li et al., 2023; H. Lin et al., 2019; Lu et al., 2023), self-disclosure in travel influencer marketing remains understudied. To fill this gap in the literature, the current study evaluates how influencers’ intimate self-disclosure can enhance perceptions of credibility through the ability to create content that is relevant to their followers. We address a main research question in line with this aim: How can congruence and competence help influencers manage perceptions of credibility when embedding intimate information in their social media recommendations? Specifically, we introduce and test a conceptual model that incorporates intimate self-disclosure, perceived content-expertise congruence, competence need fulfillment, and perceived credibility, responding to the calls for more research on the effectiveness of travel and tourism influencer marketing (Gretzel, 2018; Schivinski et al., 2020). We define influencers’ content – expertise congruence as the extent to which the content shared by an influencer aligns with the expertise they are known for on social media, whereas competence need fulfillment is understood as the extent to which individuals feel a sense of mastery, achievement, and effectiveness in their activities (Reis et al., 2000; Ryan & Deci, 2020). Building on these relationships, we investigate whether influencers’ content-expertise congruence serves as the mechanism that explains the impact of intimacy on perceived credibility. Additionally, we examine whether perceptions of an influencer’s credibility are contingent on the degree to which consumers experience a strong sense of competence when viewing the influencer.

Shedding light on the impact of self-disclosure by travel influencers, we contribute to the theoretical backgrounds of Self-determination Theory (Deci & Ryan, 2000) and the Elaboration Likelihood Model (Petty & Cacioppo, 1986) by introducing competence need fulfillment as an important variable in reducing the negative effects of intimate self-disclosure. In this regard, we introduce an alternative perspective to the research landscape surrounding influencer self-disclosure, which has predominantly emphasized on the relationship-related outcomes of self-disclosure (e.g. J. Kim & Song, 2016; Leite & Baptista, 2022b). We also address the concerns raised in previous studies regarding the drawbacks of self-disclosure (AlRabiah et al., 2022; Johnson et al., 2022; Leite et al., 2022). Our contribution presents empirical evidence that elucidates strategies for mitigating potential credibility damage caused by incongruent self-disclosures.

Theoretical background

The importance of perceived credibility in influencer marketing

Influencer marketing has emerged as a highly influential and effective marketing technique, enabling brands to connect with consumers at a deeper level through personalized and interactive content (Shankar et al., 2021). Research in this field has increasingly demonstrated the power of influencers in marketing communications efforts. Recent studies have even shown the power of influencers over traditional celebrity endorsements (see Boerman, 2020; Djafarova & Rushworth, 2017; Evans et al., 2017; Schouten et al., 2020). As an illustration, Schouten et al. (2020) discovered that influencer endorsements resulted in greater trustworthiness compared to celebrity endorsements. This trust can be built from influencers’ knowledge and expertise related to a specific field of knowledge (Djafarova & Rushworth, 2017). Thus, being perceived as a trustful source of information is what makes influencer marketing a powerful resource for brand managers (De Veirman et al., 2017; Djafarova & Rushworth, 2017; Uzunoğlu & Misci Kip, 2014).

Source credibility is often leveraged to enhance the efficiency of endorsements (Ohanian, 1990). The construct of source credibility is constituted by three fundamental dimensions i.e. firstly, attractiveness, which pertains to the perceived physical appeal of an endorser; secondly, trustworthiness, which is associated with characteristics such as honesty and the level of trust consumers place in an endorser; and thirdly, expertise, which concerns the extent to which an endorser is regarded as having legitimate knowledge, experience, and skills relevant to the product or service being promoted (Ohanian, 1990). Following that, people generally perceive information from dependable sources to be more trustworthy than other forms of information (Chung & Cho, 2017); the benefits of source credibility have been explored extensively over the years. With the rise of influencer marketing, research has shown that influencer credibility perceptions play a significant role in generating favorable outcomes for influencers, including positive attitudes toward them and favorable word-of-mouth (Taillon et al., 2020). Previous research has also demonstrated the benefits of influencers’ credibility for the brands they partner with, such as enhanced consumers’ purchase intentions (Leite & Baptista, 2022a; Schouten et al., 2020; Sokolova & Kefi, 2020; Weismueller et al., 2020), positive attitude toward the promoted brand (Munnukka et al., 2019), followers’ trust towards branded posts generated by influencers (Lou & Yuan, 2019), increased brand satisfaction, brand image, brand trust (Leite & Baptista, 2022a; Wiedmann & von Mettenheim, 2020), and self-brand connections (Leite & Baptista, 2022b).

The interactive and personalized communication that influencers establish with their followers plays a vital role in driving positive marketing outcomes (Breves et al., 2019). Interactive platforms have allowed influencers to share more than ever, offering managers an excellent opportunity to benefit from this personalized and influential content (Leite & Baptista, 2022a). Frequently, influencers employ self-disclosure as a communication strategy, demonstrating their concern for how they are perceived as reliable sources of information and advice by their followers (Bickart et al., 2015). However, the literature examining the extent to which self-disclosure influences perceptions of source credibility is still an under-studied area. Therefore, understanding how influencers can communicate with their followers more effectively is key to ensuring more positive outcomes for the influencers’ credibility.

The consequences of influencers’ self-disclosure

Researchers have extensively explored self-disclosure using various approaches to investigate this topic (e.g. J. Kim & Song, 2016; R. Lin & Utz, 2017; Omarzu, 2000; Wheeless & Grotz, 1976). In the current study, we place particular emphasis on the intimate aspect of self-disclosure, as travel influencers frequently share significant aspects of their private lives with their followers. This includes divulging personal struggles like depression, details about their relationships, and expressing emotions such as anger, sadness, and distress. While some provide only superficial information about their personal lives, others appear to be open books to their followers. This way, travel influencers’ intimate self-disclosure happens when influencers reveal different levels of intimacy such as self-disclosing factual (personal information and facts about oneself), emotional (feelings and emotions), and cognitive (private thoughts and opinions) information about themselves (Leite & Baptista, 2022b; Morton, 1978), which can range from surface-level to central details about their lives (Altman & Taylor, 1973). In this study, self-disclosure intimacy is specified by the extent to which influencers share intimate, personal, or private information on social media (Bazarova, 2012).

Past research in influencer marketing has mainly concentrated on the relational outcomes of self-disclosure. Studies have shown that when influencers reveal personal content about themselves, people can feel that they are being open about their lives and see them as more relatable and approachable. These studies have shown a positive link between self-disclosure and relationship-related variables such as followers’ attachment to the internet celebrity (Chen et al., 2021), feelings of parasocial relationships towards the influencer (Chung & Cho, 2017; M. Kim & J. Kim, 2020; Leite & Baptista, 2022a, 2022b; Penttinen et al., 2022), and parasocial interactions with the internet celebrity (J. Kim & Song, 2016; E. S-T. Wang & Hu, 2021). This phenomenon is also observed in the travel marketing context, where studies have shown that the intimate self-disclosure of travel media figures enhances the parasocial relationship between audiences and them (Lu et al., 2023). Self-disclosure helps reinforce social connections between influencers and their audience, as consumers often feel valued when influencers share intimate details about themselves (Leite & Baptista, 2022a). While prior studies have made significant progress in assessing the impact of self-disclosure on relational aspects, less is understood about what happens when travel influencers include intimate content in their social media recommendations and how this affects perceptions of credibility.

When evaluating the influence of self-disclosure on credibility, results among the few existing studies vary. For example, AlRabiah et al. (2022) have demonstrated that increasing the breadth and depth of social media self-disclosure was viewed as inappropriate, reducing trust in the influencer. Johnson et al. (2022) found that including self-disclosure in a recommendation generated less trustworthiness but did not yield significant differences in the influencer’s expertise, both aspects of credibility. Leite et al. (2022) found that high levels of self-disclosure reduced perceptions of the influencer’s credibility. These studies generally contribute to the understanding that influencers’ self-disclosure can negatively affect perceptions of credibility. However, Penttinen et al. (2022) demonstrated that the inclusion of self-disclosure in online reviews did not directly impact source credibility. Instead, this effect was found to be positively mediated by parasocial interactions. Leite et al. (2022), for instance, found that, when appropriate, self-disclosure can increase perceptions of relatedness and, subsequently, credibility. These studies expand upon previous research, demonstrating how self-disclosure enhances credibility by considering relationship-related factors. However, a key question remains: how can influencers’ intimate self-disclosure boost credibility without relying solely on strong connections with followers? To address this, we introduce two crucial factors: content-expertise congruence and competence-related need fulfillment. These factors are relevant as they are somewhat reliant on influencers’ abilities to create and deliver online content. Therefore, we expect that influencers’ self-disclosure affects their credibility not only through audience connection but also by shaping how the audience assesses their content.

The main effect of intimate self-disclosure on perceptions of credibility

Considering that sensitive information frequently encompasses personal vulnerabilities (Omarzu, 2000), we anticipate that intimate self-disclosure can be detrimental within the context of social media recommendations. This happens because revealing intimate content embedded in social media recommendations can reveal an unappealing side of the influencer, which can be interpreted as a weakness or sign of powerlessness. It is important to note that social media influencers often present a curated image of themselves, and intimate self-disclosure can disrupt this image, potentially harming their credibility. The literature has demonstrated that the effectiveness of an influencer’s persuasive communication relies on their perceived credibility as a trustworthy source of advice (Djafarova & Rushworth, 2017). Therefore, sharing sensitive content can diminish perceptions of the influencer’s cognitive abilities to endorse products and services on social media (Leite et al., 2022). In essence, including intimate content in recommendations may lead the audience to doubt their ability to effectively endorse products and services, a crucial aspect of their role as influencers. Drawing on the preceding discussion, we hypothesize the following:

H1.

Social media recommendations, which include intimate content (as opposed to those without intimate content) lead to fewer perceptions of influencers’ credibility.

The mediating role of congruence between influencers’ content and expertise

Influencer marketing has explored congruence mainly from the perspective of whether endorsers are congruent with the products they promote (De Cicco et al., 2020; D. Y. Kim & Kim, 2020; Martínez-López et al., 2020; Park & Lin, 2020; Schouten et al., 2020). For example, the benefits of congruence between an influencer and a sponsored product include a positive attitude towards the advertised product (Breves et al., 2019; D. Y. Kim & Kim, 2020), increased willingness to seek out additional information regarding the product (Martínez-López et al., 2020), positive attitudes toward the influencer and intention to continue to follow the influencer (De Cicco et al., 2020), increased trust (Martínez-López et al., 2020), and increased perceptions of the influencer’s credibility (Breves et al., 2019; De Cicco et al., 2020; Park & Lin, 2020). In travel and tourism marketing, the congruence between influencers and consumers and between influencers and destinations is an important determinant of positive visit intentions toward the endorsed destinations (X. Xu & Pratt, 2018).

In the current study, we examine a form of congruence that has not been previously explored, which we refer to as “influencers’ content-expertise congruence.” Influencers are known as content creators, which makes them notorious in a field of expertise they have established a career in, such as travel, beauty, food, fitness, and parenting. This way, influencers often provide their followers with knowledge on the niche of their expertise in the form of tutorials–, tips–, and reviews – related content. We define influencers’ content – expertise congruence as the extent to which the content shared by an influencer aligns with the field of knowledge over which they have been able to develop a career and are known (Micallef et al., 2024; Zhang et al., 2017).

We argue that the congruence between their content and expertise can explain the adverse impact of intimate self-disclosure on influencers’ credibility. While traditional celebrities have become influential mainly through traditional media channels, such as television, influencers have built their influence by producing social media content. In general, influencers expand their reach by crafting personalized content grounded in their expertise within a specific field (Jun & Yi, 2020). By positioning themselves as representatives of specific areas of interest (Schouten et al., 2020), influencers establish a strong link between their image and content-sharing practices (Burgoon, 2016; De Cicco et al., 2020), shaping their identity in followers’ minds (Tafesse & Wood, 2021). Hence, in an environment where influencers are known by their domain of interest, followers may expect influencers to deliver content related to that area of knowledge.

Research on teacher self-disclosure and its impact on credibility may provide insight into this matter. Klebig et al. (2016) found that the relevance of teacher self-disclosure positively correlated with perceived professor competence. When teachers linked their self-disclosures to course material, such as using personal examples to illustrate concepts, students viewed them as more competent. This finding underscores the importance of congruence between a professor’s self-disclosure and their course material in shaping perceptions of their competence. In this light, when influencers’ recommendations include content perceived as too distant from their main domain of interest, it contradicts followers’ expectations of relevant content. For example, consumers may react negatively towards an influencer that includes personal content in their recommendations because revealing oneself intimately may not be seen as congruent with the influencer’s expertise. This means that the negative influence of intimate self-disclosure on influencers’ credibility is determined by how relevant such content included in social media recommendations is to the influencer’s expertise. More formally,

H2.

Social media recommendations, which include intimate content (as opposed to those without intimate content) diminish perceptions of credibility due to the perceived incongruence between influencers’ content and expertise.

The moderating role of competence need fulfillment

Self-determination Theory (Deci & Ryan, 2000; Reis et al., 2000) focuses on innate and enduring human motivations for learning and development. To enhance these motivations, it is essential to consider specific fundamental psychological needs that are unique in their universality, innateness, and enduring characteristics (Deci & Ryan, 2000; Reis et al., 2000; Ryan & Deci, 2020). The inherent psychological need for competence is fulfilled by environments that afford challenges and growth opportunities where people can have the feeling of mastery, achievement, and effectiveness in their activities (Reis et al., 2000; Ryan & Deci, 2020). For example, consumers fulfill their competence needs by perceiving an influencer’s content as informative (Ki et al., 2020). Building on this principle, we understand that influencers have the potential to assist individuals in achieving their intrinsic objectives and satisfy their basic human needs, especially in fulfilling their followers’ competence needs. Industry research indicates that a primary driving force behind consumers’ decision to follow influencers is the desire to acquire new knowledge. This is closely followed by the pursuit of updates on current events, discovering new brands and products, seeking motivation or challenges, staying informed on professional news, and engaging in activities, such as following workout routines (Global Web Index, 2020). For instance, followers expect creators to produce more “how-to” tutorials. This underscores the significance of generating content that enriches consumers’ knowledge.

Previous research on basic psychological needs has traditionally concentrated on individual well-being (e.g. Deci & Ryan, 2000) and relational aspects (e.g. La Guardia et al., 2000; Thomson, 2006) as the outcomes of fulfilling one’s basic needs. For example, Thomson (2006) employed the theory of self-determination to advance the understanding of whether celebrity brands that fulfill consumer basic needs influence the intensity of attachment to a celebrity. This research demonstrates that celebrities who do not suppress individuals’ feelings of competence tend to encourage stronger consumer attachments towards the celebrity (Thomson, 2006). Recently, within the scope of influencer marketing, Ki et al. (2020) supported the findings from Thomson (2006) by showing that social media influencers who can encourage feelings of competence also foster the development of attachment bonds from followers towards them.

The current study argues that competence can be a relevant factor in mitigating the adverse effects of influencers’ intimate self-disclosure. Based on this understanding, we propose that individuals who feel a strong sense of competence when seeing, hearing, or thinking about the influencer are more likely to view the influencer’s intimate content as relevant and aligned with their expertise, potentially enhancing their credibility in the eyes of the audience.

The rationale for this effect is based on the Elaboration Likelihood Model (ELM) (Petty & Cacioppo, 1986), a key theory in social psychology that explains the processing of information in persuasive communication. ELM distinguishes between two persuasion routes i.e. the central route, where individuals carefully consider relevant arguments, and the peripheral route, where they rely on environmental cues. The ELM suggests that in high elaboration likelihood (motivated individuals), people take the central route, engaging in deep thinking, prioritizing argument quality when a message is personally relevant, and investing cognitive effort in analysis. In low elaboration likelihood (less motivated individuals), people rely on heuristic cues in the peripheral route to form their perceptions, lacking the motivation or ability for in-depth processing. Hence, when motivation and/or cognitive capacity decrease, peripheral cues gain more importance in persuasion (Petty & Cacioppo, 1986).

In line with the ELM, our argument revolves around the idea that individuals who feel highly competent when engaging with an influencer tend to rely more on the influencer’s content that aligns with their competence needs. They see the influencer as a promoter of effectiveness and achievement. Consequently, these individuals are more likely to follow a central route (Petty & Cacioppo, 1986) when evaluating the influencer’s recommendations, focusing on the core message (i.e. informative travel content), while paying less attention to peripheral elements like personal stories. Their strong sense of competence drives them to process information that satisfies their feelings of mastery, accomplishment, and effectiveness (Reis et al., 2000; Ryan & Deci, 2020), thus engaging in a detailed analysis of travel advice through the central route. In contrast, those with lower competence are more inclined to be influenced by peripheral cues, such as personal stories. Given this, as individuals who experience a stronger competence are focused on processing the informative travel content (i.e. central content), they will perceive the content as more congruent with the influencer’s expertise assigning less significance to intimate content (i.e. a peripheral cue). This shift in attentional focus can be explained through the ELM as a preference for the central processing route, where individuals prioritize the core message (i.e. travel advice) over peripheral, intimate content.

To summarize, perceptions of an influencer’s credibility depend on how individuals feel a sense of competence when seeing, hearing, or thinking about the influencer. If individuals feel a strong sense of competence, more intimate self-disclosure leads to greater perceptions that such content is relevant to the expertise of the influencer (see Figure 1 for the conceptual model). Taken together, we present the following hypothesis:

Figure 1. Conceptual model.

H3.

The detrimental impact of intimate content on perceived congruence will be less pronounced among individuals who experience a higher (as opposed to lower) sense of competence fulfillment.

Methodology

Sample

The study sample was sourced from the Amazon Mechanical Turk (MTurk) platform and participants were compensated with a nominal payment. In line with past studies on MTurk (Kees et al., 2017; Penttinen et al., 2022; Pontes & Williams, 2021), we followed participant recruitment best practices: (1) location in the U.S.; (2) at least 97% HIT approval rate; (3) have a number of HITs approved higher than zero. After excluding one duplicated Internet Protocol (IP) address, three participants who were not social media users, and 13 people who were unable to remember the name of the influencer used in the scenario, the sample we used in our analysis included 212 participants (60.4% females; mean age: 36.46, SD = 11.14). Following previous research (De Cicco et al., 2020), we ensured that the participants were active social media users. Participants’ social media usage is as follows: 85.4% reported being frequent social media users, spending a minimum of 4 hours per week; 84.4% reported using social media in the 6 hours preceding their response to the survey. The most used platforms were YouTube (82.5%), Facebook (82.1%) and Instagram (76.4%).

Design and procedure

The study employed a two-cell between‐subjects experimental design (intimate vs. without intimate content) with a continuous variable (competence need fulfillment). Intimacy was manipulated at two levels: travel recommendations with intimate versus without intimate content. Travel recommendations without intimate content mainly focus on the influencer’s travel preferences, providing advice on interacting with locals and suggesting the best places to visit. In contrast, travel recommendations with intimate content center on deepening the intimacy of the influencer’s travel preferences. This involves disclosing romantic involvements during a trip and sharing how the recommended destination holds special personal memories (Leite et al., 2022; X. Ma et al., 2016).

Initially, participants were presented with an influencer’s profile and asked to imagine following them on Instagram. Subsequently, they were instructed to envision encountering a series of the influencer’s social media posts on Instagram. Participants were then randomly assigned to one of two experimental scenarios, with both scenarios containing similar text about travel recommendations. The variations between the scenarios involved the presence or absence of intimate content. Additional details regarding these manipulations can be found in the Appendix.

Measures

After viewing the manipulations, participants responded to the influencer’s credibility scale from Ohanian (1990), consisting of fifteen 7-point semantic differential scales. The scale quantifies participants’ perceptions of the influencer’s credibility by evaluating their perceived attractiveness, trustworthiness, and expertise. We then asked participants about the congruence between the influencer’s content and her field of knowledge with two items adapted from Escalas and Bettman (2017), anchored by 1 (not well at all) and 5 (extremely well). Participants also answered to the competence need fulfillment scale adapted from Thomson (2006), comprising five items rated on a scale anchored by 1 (strongly disagree) and 7 (strongly agree) (e.g. When I see, hear, or think about Sophia … I feel very capable in what I do). Additional details regarding these measurement scales can be found in the Appendix.

To check the success of the manipulation, we used a self-disclosure intimacy scale adapted from Bazarova (2012). The measurement scale comprised three items (α = 0.83), each rated on a 7-point semantic differential scale (e.g. ranging from “non-intimate” to “intimate,” “impersonal” to “personal”). Using a 7-point Likert scale, participants reported on two items whether they believed the manipulation scenario to be realistic (Leite et al., 2022). Using the mid-point of the scale (4) as a comparison value, one sample t-test results show that participants believed the scenario to be realistic or similar to a post/profile they encountered previously on social media (M = 4.89, SD = 1.47, t(211) = 8.86, p < 0.001). Finally, participants responded to questions regarding their demographic profile and social media use.

Results

Manipulation check

The results of an independent t-test indicated that the social media recommendations containing intimate self-disclosure received significantly higher ratings than those without such disclosures (M_intimate = 5.96, SD = 1.34 versus M_nonintimate = 3.78, SD = 1.50, t(210) = −11.11, p < 0.001). Levene’s test assumed that the variances between the groups were equal, F(1,210) = 3.62, p > 0.05 (N_{intimate =} 104, N_{nonintimate =} 108). These results confirmed that the manipulation used in the study worked as planned.

Furthermore, we conducted an independent t-test to confirm that our independent variable did not influence the fulfillment of the competence need. The results demonstrated that perceptions of competence did not differ between the scenarios (M_intimate = 4.30, SD = 1.56 versus M_nonintimate = 4.54, SD = 1.54, t(210) = 1.11, p = 0.27). Levene’s test assumes that the variances between the groups were equal, F(1,210) = 0.43, p > 0.05 (N_{intimate =} 104, N_{nonintimate =} 108).

Source credibility

A one-way ANOVA revealed statistically significant main effects of intimate self-disclosure on the influencer’s credibility such that the posts containing intimate content resulted in lower ratings of the influencer’s credibility in comparison with posts that do not include intimate self-disclosure (M_intimate = 4.54, SD = 1.34 versus M_nonintimate = 5.14, SD = 0.95; F(1, 210) = 13.88, p < 0.001, η_p² = 0.06). This result supports Hypothesis 1.

The role of congruence

A one-way ANOVA revealed statistically significant main effects of intimate self-disclosure on the influencer’s content – expertise congruence, such that the posts embedding intimate content were evaluated as less congruent with the influencer’s expertise than the posts that do not include intimate self-disclosure (M_intimate = 2.63, SD = 1.27 versus M_nonintimate = 3.63, SD = 0.91; F(1, 210) = 43.54, p < 0.001, η_p² = 0.17).

More importantly, we then examined whether perceived congruence between influencers’ content and expertise mediated the impact of posts containing intimate self-disclosure on the influencer’s credibility. The study employed a mediation analysis using PROCESS Model 4 (Hayes, 2018; using 5,000 bootstrap samples) with social media posts including intimate content (without intimate = 0, intimate = 1) as the independent factor, perceived congruence between influencers’ content and expertise as the mediator, and consumers’ perceptions of influencers’ credibility as the dependent variable.

Intimate (vs. without intimate) self-disclosure decreased perceptions of congruence between influencers’ content and expertise (b = −1.00, SE = 0.15, t(210) = −6.59, p < 0.001). The impact of intimate content on consumers’ views of influencers’ credibility was mediated by the influencer’s content-expertise congruence (b = −0.79; SE = 0.13; 95% CI: [−1.07, −0.54]). This finding is supportive of Hypothesis 2.

Competence need fulfillment

As we aimed to offer insights into how influencers can maintain their credibility when sharing intimate information in social media recommendations, our findings provide new insights on how to mitigate these negative effects. Hypothesis 3 proposed that competence need fulfillment attenuates the negative impact of intimate content on perceived congruence between influencers’ content and expertise. To test this hypothesis, we conducted a moderated mediation analysis (using PROCESS Model 7 by Hayes, 2018 with 5,000 bootstrap samples) with social media posts including intimate content (without intimate = 0, intimate = 1) as the independent factor, perceived congruence between influencers’ content and expertise as the mediator, consumers’ perceptions of influencers’ credibility as the dependent variable, and competence need fulfillment as the moderator.

Results demonstrated that all direct effects on congruence were statistically significant. Specifically, the model (F (3,208) = 45.43, p < 0.001, R² = 0.39) revealed that intimate (vs. without intimate) content decreased evaluations of congruence (b = −1.72, SE = 0.39, t(208) = −4.35, p < 0.001), whereas higher (vs. lower) competence increased evaluations of congruence between influencers’ content and expertise (b = 0.26, SE = 0.05, t(208) = 4.50, p < 0.001). The two-way interaction between intimacy and competence was significant (b = 0.18, SE = 0.08, t(208) = 2.15, p = 0.03).

Analysis of the conditional effect of intimate content at each level of competence need fulfillment demonstrated that the effect of intimacy on congruence is statistically significant and negative for all levels of competence (low_–1SD: b = −1.20, SE = 0.18, t(208) = −6.48, p < 0.001; medium_M: b = −0.91, SE = 0.13, t(208) = −7.01, p < 0.001; high_+1SD: b = −0.63, SE = 0.18, t(208) = −3.42, p < 0.001). However, as the level of competence need fulfillment increases, the negative impact of intimacy on congruence becomes smaller. This result is consistent with the prediction that competence needs fulfillment lessens the negative effect of intimacy on perceived congruence between influencers’ content and expertise. This interaction is shown in Figure 2.

Figure 2. The effect of intimate content and competence need fulfillment on perceived congruence between the influencer’s content and expertise.

Finally, results show that the influence of intimate content on credibility through congruence is attenuated as competence need fulfillment increases from low (ind.b_–1SD = −0.95; 95% CI: [−1.33, −0.61]) to higher levels of competence (ind.b_+1SD: = −0.50; 95% CI: [−0.79, −0.22]). The direct effect of intimate content on credibility was non-significant (b = 0.20, SE = 0.11, t(209) = 1.77, p > 0.05). The index of moderated mediation did not include zero (index = 0.14, SE = 0.07, 95% CI: [0.0006, 0.2986]). These findings support Hypothesis 3 (see Figure 3).

Figure 3. Moderated mediation analysis of the impact of intimate content and competence need fulfillment on the influencer’s credibility via the influencer’s content-expertise congruence.

Discussion

The current study investigated what happens when travel influencers include intimate content in their recommendations. Our findings reveal that embedding intimate content on social media recommendations can jeopardize perceptions of influencers’ credibility because consumers perceive such content as not congruent or relevant to the expertise of the influencer. This means that including intimate content in recommendations does not always contribute to forming positive evaluations. When the content was solely focused on the influencer’s travel preferences and tips (i.e. providing advice on interacting with locals and suggesting the best places to visit), such content was perceived as more congruent with the influencer’s expertise. However, when such preferences and tips included more intimate information (i.e. disclosing romantic involvements during a trip and sharing how the recommended destination holds special personal memories), such content was perceived as less congruent with the influencer’s expertise, damaging perceptions of the influencer’s credibility. This implies that consumers are more receptive to social media content that is both relevant and adds to the expertise of the influencer.

In addressing our primary research question, we discovered that content congruence plays a vital role in shaping perceptions of credibility, especially when consumers perceive that the influencer fulfills their competence needs. Our findings indicate that exposure to travel recommendations featuring intimate self-disclosure enhances influencer credibility through congruence, but primarily for those with a high sense of competence fulfillment. In summary, these findings emphasize the importance of both content-expertise congruence, and the fulfillment of competence needs in elucidating how self-disclosure impacts credibility. The findings highlight that influencers’ intimate self-disclosure can boost perceptions of credibility by creating relevant content for their followers, rather than relying solely on the establishment of strong follower relationships.

Theoretical implications

Our research holds significant theoretical implications for both influencer and travel marketing research. In response to the call made by earlier travel research (J. Xu et al., 2023; Zhou et al., 2021), our study emphasizes the importance of investigating effective communication strategies among recommenders, particularly focusing on influencers. While there has been considerable interest in investigating the impact of self-disclosure as a communication strategy (e.g. AlRabiah et al., 2022; Johnson et al., 2022; Leite et al., 2022; Lu et al., 2023; Penttinen et al., 2022), previous research has provided only limited insights into how influencers can effectively harness intimacy to establish credibility with their followers. This is particularly important in tourism and travel research, where literature on self-disclosure is scarce (Li et al., 2023; H. Lin et al., 2019; Lu et al., 2023). Considering followers’ appreciation for influencers’ personal experiences and travel preferences (J. Xu et al., 2023; Zhou et al., 2021), our research extends beyond previous findings to examine the factors influencing how intimate self-disclosure by travel influencers impacts perceptions of credibility.

Earlier research in travel and tourism marketing emphasizes the significance of congruence between influencers and consumers, as well as between influencers and destinations, as antecedents of positive visit intentions toward the endorsed destinations (X. Xu & Pratt, 2018). Our study contributes to this field by being the first to evaluate influencers’ congruence between their content and expertise. Our findings emphasize the importance of aligning an influencer’s content with their area of expertise as a key factor in shaping how credible they are perceived to be. We evaluate the role of influencers’ content – expertise congruence as a variable closely related to the aspects that make influencer marketing unique. In other words, the idea that influencers are recognized for the expertise they have cultivated in their careers can lead followers to expect content that is pertinent to that area of knowledge. Our findings offer empirical evidence highlighting the significance of influencers sharing personal information that is relevant to their followers to enhance their credibility. While developing strong ties with followers is important for influencers’ credibility, as emphasized in previous studies (e.g. Penttinen et al., 2022), not all influencers can sustain active reciprocity with their followers (Leite & Baptista, 2022b), making it challenging to establish and nurture strong, progressive relationships with their audience. In this regard, we demonstrate that congruence between influencers’ content and their field of expertise is critical for the effectiveness of travel influencers’ communication strategies.

Furthermore, past studies offer few insights into the boundary conditions that affect how consumers perceive the inclusion of self-disclosure in social media recommendations (e.g. AlRabiah et al., 2022). In view of this, we contribute to the literature by evaluating one important boundary condition to this effect: competence need fulfillment, a variable capable of reducing the negative effects of intimate self-disclosure. Drawing on the Self-determination Theory (Deci & Ryan, 2000; Reis et al., 2000) and the Elaboration Likelihood Model (Petty & Cacioppo, 1986), as well as studies assessing the advantages of media figures fulfilling individuals’ psychological needs (Ki et al., 2020; Thomson, 2006), we offer a unique interaction mechanism of competence need fulfillment and self-disclosure to demonstrate that influencers’ intimate self-disclosure can bolster perceptions of credibility without relying solely on their capacity to forge relational bonds with their followers. This finding is relevant, given that it is somewhat reliant on influencers’ abilities to create and deliver online content. Therefore, our research fills a notable gap in the current literature by showing that influencers’ self-disclosure affects their credibility by shaping how the audience assesses their content.

Managerial implications

What happens when travel influencers include intimate and personal content in their social media recommendations? Are influencers perceived as more or less credible when they include personal content in their travel recommendations? These questions may arise for both marketers and influencers looking to deliver messages that will resonate positively among their audience.

While the inclusion of intimate self-disclosure in travel recommendations may lead to lower perceptions of the influencer’s credibility, our study reveals that influencers can mitigate this detrimental effect by creating content closely related to the influencer’s area of expertise. This is particularly important for individuals who experience a strong sense of competence when engaging with the influencer. These individuals are more likely to focus on the influencer’s core message – informative travel content – processing information that aligns with their feelings of mastery, accomplishment, and effectiveness (Ryan & Deci, 2020). Therefore, we suggest that social media marketers should use the fulfillment of followers’ competence needs in strategic ways, focusing on growth-oriented environments that make people feel capable and skilled. Through simple yet effective changes, travel influencers can continuously meet their followers’ needs for growth. Various opportunities arise by recognizing that followers who feel competent tend to respond more positively to influencers. In our study, a sense of competence among social media users leads them to perceive influencer content as more relevant, thereby enhancing perceptions of credibility. Building on this, one effective approach for travel influencers is to create informative and educational content that empowers followers to acquire new skills or gain knowledge in their areas of interest. This demonstrates the influencer’s commitment to their personal growth. In particular, travel influencers can enhance their credibility and relevance by incorporating challenges, quizzes, and contests that encourage their audience to share their experiences and expertise related to promoted products or services. This strategy helps users showcase their competence, especially in providing comprehensive travel guides and tips, detailed itineraries, cost breakdowns, safety advice, and more. By consistently offering informative content, influencers can effectively meet their followers’ competence needs (Ki et al., 2020), ensuring that their content remains relevant and aligns with their expertise. This approach offers fresh insights into how influencers and marketers in the travel and tourism field can more effectively incorporate personal and intimate stories into their content.

Limitations and future research

The current study has provided valuable insights into mitigating the adverse impact of influencers’ intimate self-disclosure on their perceived credibility, but it does have some limitations. In line with previous research (e.g. De Jans et al., 2020; De Veirman & Hudders, 2019; De Veirman et al., 2017), we employed a fictitious influencer in this study to examine the effects of the variables of interest while controlling for prior influencer knowledge and eliminating potential interference from extraneous variables. Using a fictitious influencer and a hypothetical scenario rather than a real-life context may have constrained the external validity of the study. Nevertheless, scenario-based studies are valuable for enhancing internal validity by allowing a level of control that is often unattainable through other methods (Pontes & Williams, 2021). To bolster the internal validity and relevance of the manipulation stimuli, we followed the approach proposed by De Veirman et al. (2017) by crafting a fictitious influencer’s profile biography that closely resembled that of a real influencer. For broader generalizability, future research could investigate the effects of influencers’ self-disclosure on consumers’ perceptions of influencer credibility, both for familiar and unfamiliar influencers. Consumers’ responses regarding what they consider congruent content may differ when encountering a first-time influencer compared to a familiar one (Rains & Brunner, 2018; Utz, 2015).

Consistent with Nah (2022), our current research aimed to ensure that the only distinction between the manipulations was the presence or absence of intimate self-disclosure. As a result, the word count of the text utilized in the manipulations differed across conditions. While this approach may present a limitation, it was essential to create the necessary contrast between scenarios with and without intimacy. It is worth noting that this manipulation method aligns with recent studies that have similarly varied the length of self-disclosure manipulations (e.g. Huaman‐Ramirez et al., 2021; S. S. Lee & Johnson, 2021; Penttinen et al., 2022), particularly within the field of tourism research (Li et al., 2023).

Finally, our choice to depict a female influencer is based on several considerations. First and foremost, women tend to engage in more natural and intimate self-disclosure, making it well-aligned with this portrayal (Caltabiano & Smithson, 1983). Women have been observed to self-disclose more intimately than men on various social media platforms (Y. C. Wang et al., 2016). Secondly, the influencer market is predominantly composed of women (Hudders & De Jans, 2021), and a substantial portion of Instagram’s global (51.4%) and U.S. (57.9%) users are female (Statista, 2021a, 2021b). Therefore, it is more appropriate to do our analysis with a female influencer. Nonetheless, future research could delve into the impact of influencer gender on the effects identified in this study, particularly in the context of same-sex and opposite-sex influencers (Baxter et al., 2022; Hudders et al., 2020).

Disclosure statement

No potential conflict of interest was reported by the authors.

Appendix

Manipulations

Table

Travel recommendations without intimate content	Travel recommendations including intimate content
Influencer:	Influencer:
Hey guys,	Hey guys,
This week I will be giving travel tips about Thailand.	This week I will be giving travel tips about my recent trip to Thailand.
Tip 1 – Meeting local Thai people.	Tip 1 – Meeting local Thai people.
The best way to meet locals is through food.	The best way I’ve found to meet locals is through food.
In Bangkok, for example, go to a local food stall or restaurant and you will find it easier to interact with locals.	In Bangkok, for example, go to a local food stall or restaurant and you will find it easier to interact with locals.
You’ll get yourself amazed by being surrounded by locals.	You’ll get yourself amazed by being surrounded by locals.
Meeting locals is the best thing you can possibly do!	In one of my visits to one of these local restaurants, I met a guy who finally made me feel alive after years! No one has ever made my heart race like this guy. We’ve been seeing each other for a while, and we are planning to make it official! This was the best thing it has ever happened to me! OMG! I have never told this to anyone before!
Tip 2 – Beaches in Thailand.	Tip 2 – Beaches in Thailand.
Koh Lipe Island is the best place to go to in Thailand.	Koh Lipe Island is the best place to go to in Thailand.
Three days is enough to have an amazing experience in the island.	I spent three days there. I had an amazing experience in the island.
No doubt the beaches will be the most beautiful you’ll ever see in your life.	No doubt the beaches were the most beautiful I’ve ever seen in my life.
I strongly recommend you traveling to the island.	The island reminds me of a special moment of my life, something very private that I’m going to reveal to you.
It’ll be the best experience you’ll ever have!	My first sexual experience happened in an island … I was so comfortable and secure about my body that we ended up spending a wonderful night together. It was one of the best experiences I’ve ever had!

Table

Constructs, Scales, and Items	Factor Loading	Cronbach’s α	AVE	CR
Influencer Credibility - Ohanian (1990)
Unattractive-Attractive	0.68	0.95	0.61	0.96
Not Classy-Classy	0.63
Ugly-Beautiful	0.75
Plain-Elegant	0.47
Not Sexy-Sexy	0.78
Undependable-Dependable	0.70
Dishonest-Honest	0.64
Unreliable-Reliable	0.64
Insincere-Sincere	0.75
Untrustworthy-Trustworthy	0.86
Not an expert-Expert	0.85
Inexperienced-Experienced	0.95
Unknowledgeable-Knowledgeable	0.99
Unqualified-Qualified	0.98
Unskilled-Skilled	0.84
Content-Expertise Congruence – adapted from Escalas and Bettman (2017)
To what extent does the content shared by [influencer] in the posts match [influencer’s] field of knowledge?	0.78	0.91	0.59	0.74
Does the field of knowledge of [influencer] and the content of his/her posts fit together?	0.76
Competence Need Fulfillment – adapted from Thomson (2006)
Generally, [influencer] makes me feel very capable and effective.	0.65	0.93	0.70	0.92
[influencer] makes me feel adequate or competent.	0.69
I feel that I can successfully complete difficult tasks and projects.	0.98
I feel that I can take on and master hard challenges.	0.89
I feel very capable in what I do.	0.93