Clarke Christopher E, Weberling McKeever Brooke, Holton Avery, Dixon Graham N
a Department of Communication , George Mason University , Fairfax , Virginia , USA.
b School of Journalism and Mass Communication , University of South Carolina , Columbia , South Carolina , USA.
J Health Commun. 2015;20(11):1302-9. doi: 10.1080/10810730.2015.1023959. Epub 2015 Jul 27.
Media coverage of contentious risk issues often features competing claims about whether a risk exists and what scientific evidence shows, and journalists often cover these issues by presenting both sides. However, for topics defined by scientific agreement, balanced coverage erroneously heightens uncertainty about scientific information and the issue itself. In this article, we extend research on combating so-called information and issue uncertainty using weight of evidence, drawing on the discredited autism-vaccine link as a case study. We examine whether people's perceptions of issue uncertainty (about whether a link exists) change before and after they encounter a news message with weight-of-evidence information. We also explore whether message exposure is associated with broader issue judgments, specifically vaccine attitudes. Participants (n = 181) read news articles that included or omitted weight-of-evidence content stating that scientific studies have found no link and that scientists agree that none exists. Postexposure issue uncertainty decreased-in other words, issue certainty increased-from preexposure levels across all conditions. Moreover, weight-of-evidence messages were associated with positive vaccine attitudes indirectly via reduced information uncertainty (i.e., one's belief that scientific opinion and evidence concerning a potential link is unclear) as well as issue uncertainty. We discuss implications for risk communication.
媒体对有争议的风险问题的报道往往围绕风险是否存在以及科学证据表明了什么展开相互竞争的说法，记者们通常通过呈现双方观点来报道这些问题。然而，对于已达成科学共识的主题，平衡报道错误地加剧了人们对科学信息及问题本身的不确定性。在本文中，我们以已被证伪的自闭症与疫苗的关联为例，扩展了关于运用证据权重来对抗所谓信息和问题不确定性的研究。我们考察了人们在接触包含证据权重信息的新闻消息前后，对问题不确定性（关于是否存在关联）的认知是否发生变化。我们还探究了消息曝光是否与更广泛的问题判断相关，特别是疫苗态度。参与者（n = 181）阅读了包含或省略证据权重内容的新闻文章，这些内容表明科学研究未发现关联且科学家们也一致认为不存在关联。接触消息后，所有条件下的问题不确定性均从接触前的水平下降了——换言之，问题确定性增加了。此外，证据权重消息通过降低信息不确定性（即一个人认为关于潜在关联的科学观点和证据不明确的信念）以及问题不确定性，间接与积极的疫苗态度相关联。我们讨论了这对风险沟通的启示。
