The use of emotion in health related messages: employing the exemplification theory to explain the MMR-autism debate

Abstract

Health communication messages have been found to have a significant positive impact on audiences. However, numerous situations exist in which the general population is exposed to information from non-credible sources. This initial exposure can often bias or impact subsequent searching for more information. Vaccinations have been considered effective as a result of the number of lives that have been saved by preventing life threatening diseases. However there is also a growing group of anti-vaccine sources. The rise of the internet has resulted in the growth of numerous unqualified anti-vaccine sources. Nearly 70% of the health information that people find on the internet is from non-credible sources. These messages often take the form of videos in which a person who makes a passionate claim about the side effects of vaccines uses personal experiences (exemplars). These exemplars are used to counter the volumes of scientific and clinical research which show the effectiveness of vaccinations (base-rate information). This study manipulates the usage of passionate and dispassionate exemplars and base-rate information by simulating a real-world situation. Passionate exemplars were the most likely to create fear in our audience. Increasing the passion of our base-rate presenters exhibited both positive and negative side effects.