Keywords

1 Introduction

Word-of-mouth (WOM) is one of the oldest and most important channels of information dispersion between people and is recognized as an important determinant of consumer purchase behavior. Nevertheless, traditional WOM communications are limited between network boundaries and become weaker over distance and time [1]. Development of the Internet and popularity of e-commerce have led to the growth of electronic WOM (eWOM). Even though eWOM may be less personal, mostly anonymous and happens between people with weak ties in comparison with traditional WOM, it is seen as a more powerful tool because it is credible, publicly available and has significant reach [2]. The influence of eWOM can affect attitude and purchase intention of consumers, and hence sales [3]. Therefore, eWOM communications have received much attention from scholars [1].

Even though many studies have been conducted on eWOM, a structured analysis of this research stream is still limited [3]. A review of previous literature is valuable because findings are spread across different disciplines and thus difficult to acquire a consolidated view on this topic [4]. A few attempts to assess the literature on eWOM communications have been done [3, 4]. However, these studies have not considered persuasiveness of eWOM in detail and how it is affected by social media. Hence, the objective of this paper is to provide a brief review of the exiting literature on persuasiveness of eWOM. This paper contributes to the existing literature, structuring and summarizing studies on eWOM communications, identifying existing gaps in the current research and providing directions for future studies.

The collection of appropriate research papers commenced through exploration of suitable articles found via Web of Science and SCOPUS. For this purpose the following search terms included “Electronic word-of-mouth”, “Electronic word of mouth”, “eWOM”, “Internet word-of-mouth”, “Internet word of mouth”, “iWOM”, “Online word-of-mouth”, “Online word of mouth”, “Helpful”, “Useful”, “Persuasive”, and “Credible”. Articles written in English, regardless of the research methods were collected. As a result of this search, 57 relevant scholarly articles were found that related, in various forms, to the persuasiveness of eWOM communications.

The remainder of the paper is as follows. First, the review of the literature about how consumers evaluate persuasiveness of eWOM communications is presented. After, the limitations of the existing studies are outlined with the proposed directions for future research. Finally, the paper is briefly concluded.

2 Persuasiveness of eWOM Communications

Consumers use eWOM as one of the most important sources of information to make purchase decisions [5]. Researchers suggest that consumers rely on eWOM communications if they perceive them persuasive [6]. Studies on the persuasiveness of eWOM mostly use the Elaboration Likelihood Model [7–12]. In order to be persuasive, message should be considered as helpful and credible. A number of studies prove the link between credibility and usefulness of eWOM and information adoption [6, 13, 14], which can influence consumers’ attitudes and purchase intentions.

A number of studies investigate factors which influence persuasiveness of eWOM communications [7, 11, 13]. Studies propose that message, source of information and reviewer characteristics affect perceived eWOM helpfulness and credibility [5, 13]. Also, it is found that the effectiveness of eWOM communications can be moderated by platform type and type of product [9]. Determinants of eWOM persuasiveness are presented in Table 1 and briefly discussed below.

Table 1. Determinants of eWOM persuasiveness
Full size table

Message. Quality, argument strength, content, valence and other factors can influence the persuasiveness of eWOM message. For example, from conducting an on-line survey of 159 participants of a consumer discussion forum in China, Cheung et al. [13] found that argument strengths, recommendation consistency, and rating affect credibility of eWOM. Another study by Kim and Gupta [10] found that valence and emotions embedded in the online review affect usefulness of eWOM messages. Additionally, previous studies find that reviews with negative valences have more impact on persuasiveness of eWOM compared to those with positive valences [6, 15].

Source. Characteristics of information source can affect the credibility of eWOM communications and thus persuasiveness. Existing studies focus on expertise and trustworthiness of information source [6, 8, 14]. A study conducted by Teng et al. [6] using social media platform QQ, finds that source expertness and trustworthiness, as well as source attractiveness (familiarity and likeability), social tie, and homophile influence affect eWOM persuasiveness.

Receiver. The evaluation of eWOM can vary from person to person. As a result, the same message can be considered differently by consumers. Studies find that consumers’ characteristics such as, trust propensity, previous experience with seller, prior knowledge, involvement, prior beliefs, and cultural characteristics can moderate the persuasiveness of eWOM communications [11, 15].

Development of Web 2.0 technologies and growth of social media introduced a new form of eWOM communication, social word-of-mouth [6, 21], which is “detailing evaluation by consumers about a product using social media” [21]. Using social media, consumers can communicate in online communities using different Web 2.0 technologies (recommendations, ratings, reviews, forums) [21]. Some studies investigate how social media affects eWOM persuasiveness [6, 21]. For example, a recent study conducted by Hajili [21], which used TripAdvisor as an example of a travel forum, finds that social media makes eWOM seem more credible and useful, which leads to information adoption. The results of this study show that characteristics of social media such as continuing contact, relationships with familiar peers, social media interactivity, and disclosure of individuals identity improves perceived credibility of eWOM communications.

3 Literature Gaps and Recommendations of Future Research

There are some issues, which have not yet been considered by existing studies on the persuasiveness of eWOM communications. This section highlights limitations, providing opportunities for future research.

Studies on eWOM communications have been conducted in China [1, 6, 11, 13, 17], Taiwan [5, 8, 19], South Korea [9, 12, 20], Germany [14] and USA [10, 15, 16, 18] which can limit generalizability the findings to other countries. Also, studies reported different results regarding persuasiveness of eWOM communications. For example, study [6] which is conducted in China finds that homophily of the source affects eWOM persuasiveness, while the other study [14] conducted in Germany shows the opposite results. It is important for future research to study effects of eWOM from the point of view of UK consumers to discover any differences due to cultural and social factors.

Most of the studies have considered just written eWOM [6, 7, 17, 20]. As a result, persuasiveness of visual eWOM is an under-researched area. Future research should consider the need of visual information for different industries and product categories. Also, researchers could consider how the perception of the message changes once it is presented in a visual form. Understanding consumers’ visual orientation will help to conduct effective marketing communications.

There is a lack of studies on the impact of emotions on perceived persuasiveness of eWOM. Investigating the impact of emotions on eWOM can help mangers to improve attitude towards product and brand, and increase product sales. Also, previous studies have not considered moderators of this relationship (e.g. product type).

Studies mostly employ quantitative research approach, such as surveys [1, 6, 11, 13, 14, 17, 19, 20] and experiments [5, 9, 12, 15, 16] to investigate factors influencing persuasiveness eWOM communications. Future studies can use qualitative research approach such as interviews and focus groups in order to investigate new factors which can affect persuasiveness of eWOM communications.

Some studies investigate the role social media plays in eWOM persuasiveness, using platforms such SNS, forums and chatrooms [6, 8, 21]. However, factors which affect persuasiveness of eWOM may vary as a result of differences in technology base, communications methods, and conduct of members on different platforms. As a result, future research exploring and comparing how different types of social media platforms can influence persuasiveness of eWOM communications, will allow marketers to develop better strategies for particular online platforms.

4 Conclusion

To summarize, this literature analysis presented the state of current knowledge in the evaluation of eWOM communications by consumers. The researchers show that message, source and receiver characteristics affect eWOM persuasiveness. This paper assists future research by reviewing previous studies and proposing future research directions. The review presented has been limited by space constraints but provides a useful starting point for conceptualization of a research model, which can be enhanced further by a deeper review of current research.

Attending to some of the gaps identified, the researchers now plan to focus on the effect of embedded emotions in eWOM messages on usefulness of social media eWOM in the context of UK consumers.