The effectiveness of publicity versus advertising: a meta-analytic investigation of its moderators

This study provides an answer to the question whether and under which conditions publicity is more or less effective than advertising. Advertising refers to paid communication that identifies the message sponsor, whereas publicity is communication that secures editorial space in media for promotion purposes and does not have an identifiable sponsor. The primary advantage of advertising over publicity is the sponsor's control over message content; its disadvantages are audience skepticism and lack of credibility. We investigate this trade-off between credibility effects and effects of recipients' processing and evaluation of message content. Results of a meta-analytic structural equation model show that the positive credibility effect of publicity is on average about three times as strong as the information evaluation effect, supporting the overall superiority of publicity over advertising. This effect, however, is moderated by prior knowledge and only holds for products about which recipients lack prior knowledge. The effects change for known products when advertising becomes superior. The effectiveness of publicity depends on further moderating variables. In particular, academic studies tend to underestimate the true effects of publicity over advertising due to experimental manipulations. Campaigns that combine publicity and advertising weaken the effects of publicity, whereas advertorials (i.e., advertisements disguised as editorial material) are more effective, since they combine the advantages of both publicity and advertising. The results have theoretical and practical implications.