Credence Services: Content, credibility, and usefulness of online reviews

Credence products are those whose quality is difficult or impossible for consumers to assess, even after consuming the product (Darby & Karni, 1973). For example, it is difficult to assess the technical skill and knowledge of a physician even after a visit. This research is focused on the content, structure and consumer perceptions of online reviews for credence services. We start by examining how the content and structure of real online reviews of credence services systematically differs from those of experience services (Nelson, 1970). We find that online reviews of credence services are more likely to contain unsupported claims than reviews of experience services. We experimentally examine consumer perceptions of reviews, varying both their structure and content. Consumers rationally discount the credibility of credence claims when presented with short, simple reviews but we expect more complex argument structure and inclusion of experience attributes in the review to attenuate this effect.