The effect of multiple source information on message scrutiny: The case of source expertise and likability1

Abstract

To test for the effect of multiple source information on message scrutiny, in a three-factorial experiment source likability, source expertise, and argument quality were manipulated independently. In line with predictions, results indicated heightened message scrutiny in the case of inconsistent as compared to consistent source information. Thus, argument quality affected attitudes and perceived argument strength only when the message was presented by a dislikable expert and a likable non-expert (inconsistent source information). Both measures were unaffected by argument quality when the message was presented by a likable expert and a dislikable non-expert (consistent source information). The role of multiple source information in persuasion is discussed.