Believing in Biotech

The bovine growth hormone (BGH) issue offers a good opportunity to study the credibility of information sources promoting a controversial technology to a public user group, in this case, dairy farmers. It also provides a context in a naturalistic conflict situation for examining the expertise and trustworthiness components of credibility, and how those relate to attitude similarity and extremity. The authors investigated farmers' uses of information sources in evaluating BGH, the credibility attached to various sources, and factors affecting that credibility. As hypothesized, the farmers clearly distinguished between the expertise and trustworthiness attached to BGH information sources. They also rated sources that they perceived as having attitudes similar to their own as more trustworthy but not more expert. Farmers with more extreme attitudes toward BGH significantly downgraded the trustworthiness of several institutional sources and the expertise of a broader range of sources, including certain mass media.