Determinants of the Perceived eWOM Review Credibility Part 1

Written by Luca Luzzani



In 2008 Dave Carroll, a passenger of United Airlines, had a problem with the company, since one of the baggage handlers destroyed his 3500-dollar guitar. Dave did not obtain any compensation from the airline, thus he decided to broadcast a video on YouTube, “United breaks guitars”, which went viral in a few, reaching consumers all over the world, and causing remarkable financial losses to United Airlines. (Gensler et al., 2013)

Dave’s story shows clearly the significance of electronic word-of-mouth (eWOM) nowadays, where the marketing landscape has changed. Indeed, interactive digital media platforms have created a 24/7 collaborative world, and empowered consumers to share, connect and collaborate each other (Hanna et al., 2011). In such a context, consumers trust more eWOM that traditional media (Cheung and Thadani, 2012), but, at the same time, the issue of eWOM review credibility arises, as one of the basic requirements for the adoption of the eWOM message (Lis, 2013).


What are the determinants of credibility in the eWOM review?

The purpose of the paper is to analyse one of the basic requirements involved in eWOM review adoption: credibility.

In order to do so, the first part of the research shows the differences between traditional word-of-mouth and electronic word-of-mouth, in order to provide a theoretical background, necessary to dig deeper in how credibility and eWOM communication match together.

 The second part of the paper presents a new model, which embraces the most relevant determinants of the perceived eWOM review credibility, collected through field studies by several scholars.


Consumers have the possibility to share their opinions, comments or reviews about products and services in a large number of different platforms, including weblogs, discussion forums, review websites, e-bulletin boards systems, newsgroups, and social networks (Cheung and Thadani, 2012). Prior research has already demonstrated that, online, consumers trust more eWOM than traditional media (Cheung and Thadani, 2012). Moreover, the scholars point out that consumer reviews have a significant influence on consumer purchase decisions.

eWOM stems from a traditional form of word-of-mouth (WOM), which takes place offline. For this reason, it is crucial to analyse the differences among the two forms.

One of the main characteristics of traditional WOM is the close proximity between the communication participants, where the communication is rich of social and contextual cues (King et al., 2014). Usually traditional WOM takes place in private conversations or dialogues (King et al., 2014) (Cheung and Thadani, 2012). On the other hand, eWOM consists in multi-way exchanges of information in an asynchronous mode (Cheung and Thadani, 2012). Indeed, according to Cheung and Thadani (2012), asynchronous means that sender and receiver do not have to be present at the same time or in the same place to exchange information.  This phenomenon shows one of the major characteristics of eWOM: persistence and accessibility (or observability), due to the presence of public repositories where comments and reviews are stored (King et al., 2014) (Cheung and Thadani, 2012). According to King et al. (2014), the persistence of online reviews enables to influence people also between weak ties, and not just between strong ties as it happens in  traditional WOM. Moreover, eWOM is characterised by remarkable scalability and speed of diffusion (Cheung and Thadani, 2012). Chung and Thadani (2012) specify also that eWOM communication is better measurable than offline (traditional) WOM. Indeed, it is possible to collect a large number of messages and analyse their characteristics – words used, writing style, position of the message, and so forth.

King et al. (2014) define six major characteristics of eWOM:

-          Enhanced volume: The greater the volume of messages, the greater the awareness of the product/service and, consequently, the greater the likelihood of increasing sales (Liu, 2006; cited in King et al., 2014).

-          Dispersion: Dispersion stands for the extent to which product-related conversations take place in a range of different communities.

-          Persistence and Observability

-          Anonymity and Deception: eWOM is characterized by reviews written by unknown senders.

-          Salience of valence: eWOM presents three main biases: confirmatory bias, negative bias, and under-reporting bias. The former refers to the fact that people look for affirmative evidence, in order to support their product choice. The second explains that, when people are neutral toward a certain product or service, negative reviews are seen as more salient than positive ones. Finally, the under-reporting bias stands for the tendency of reviewers of reporting either very positive or very negative comments, leaving a gap in the middle.

-          Community engagement: eWOM platforms support the creation of communities of people. In firm-customers engagement activities, this phenomenon leads to a new layer between the company and its customers, where communities mediate the engagement between the two players.

One of the approaches which can be adopted in order to study eWOM, is to consider the phenomenon as a social communication. According to Cheung and Thadani (2012), social communication implies four elements:  the source, the stimulus, the receiver, and the response. The response is the effect of the review on the receiver, and gaining a better understanding of it, can give some answers about how and when the message can be perceived as credible by the receiver. Cheung and Thadani (2012) point out that information usefulness and eWOM credibility are positively correlated with eWOM adoption. The positive relation between perceived credibility and adoption of the information has been confirmed by Lis (2013). Moreover, the adoption of the eWOM information leads to a higher probability of purchase (Lis, 2013). That is one of the reasons why the perceived credibility of the message is so crucial when investigating eWOM. Much research has been conducted in order to understand the determinants which make the receivers perceive the message as credible.