The effect of online source type on review attitude through perceived expertise and perceived trustworthiness: a suppression situation

This study suggests that online source types (typical consumer vs. expert source) can induce differential effects on two dimensions of source credibility - perceived source expertise and perceived source trustworthiness - and, hence, on messages attitudes. This was tested for online product reviewers by means of two experiments. The results revealed two competing mechanisms: A consumer source ( vs. expert source) had a positive indirect effect on review attitude through perceived trustworthiness, and a negative indirect effect through perceived expertise. In tandem, these mechanisms suppressed the relationship between source type and review attitude. This suppression situation only emerged when the expert status of the source was based on self-claims; when the expert status of the source was verified by a peer rating system, no suppression situation emerged. The theoretical, methodological and societal implications of these findings are discussed.