Multiple Sources in Advertising Appeals: When Product Endorsers are Paid by the Advertising Sponsor

Previous research has shown that respondents who are exposed to multiple sources featured in an advertising appeal engage in more diligent processing of the message arguments than those who are exposed to a single message source presenting the same basic appeal. Other research has demonstrated that the persuasive advantage of an appeal can be significantly diminished when respondents perceive that the message source is motivated by the compensation received to endorse a product. Using a 2 (Single vs. Multiple Sources) x 2 (Paid vs. Unpaid Source) between-subjects factorial design, subjects were shown a print advertisement for a new multivitamin food supplement. Results showed that subjects exposed to unpaid multiple sources generated significantly more positive thoughts and attitudes than those exposed to a similar number of sources who were paid to endorse the product. In contrast, subjects in the single-source conditions showed no significant differences in the number of thoughts and the strength of attitudes in response to paid versus unpaid message sources. Theoretical and managerial implications of these findings are discussed.