Effects of Aging and Individual Differences on Credibility Judgment of Online Health Information

Effects of Aging and Individual Differences on Credibility Judgment of Online Health Information Q. Vera Liao (liao28@illinois.edu) & Wai-Tat Fu (wfu@illinois.edu) University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA experience, and domain knowledge interact to influence credibility judgment of online information. Given that credibility judgment plays a vital role in older adults’ successful and safe consumption of online health information, a systematic study on age differences in credibility judgment will critically facilitate older adults to benefit from the massive amount of online health information for better maintenance of their health conditions. In this study, we were interested in the difference in the credibility judgment of online health information between younger and older adults, as well as the underlying factors of such differences. To this end, we collected the credibility rating and verbal protocols as younger and older adults evaluated the credibility of health information on different Websites. We analyzed the potential differences between the two groups in terms of their credibility judgment, and the strategies they used. We also studied the extent to which these differences could be explained by age-related individual differences such as their cognitive ability, Internet experience, and health related domain knowledge. Abstract We investigated the effects of aging and individual differences on credibility judgment of online health information. Analysis of credibility judgment ratings revealed that older adults were less influenced by argument strength in content messages and contextual Website features than younger adults. Verbal protocol analysis revealed that older adults tended to accept the facts they read on the Web page instead of further deliberating on their credibility. They also tended to pay less attention to contextual Website features relevant to the credibility of the information. We also found that older adults’ lower sensitivity to credibility cues on a Web page could at least be partially explained by their declined cognitive ability and lack of Internet experience. On the other hand, health-related domain knowledge was found to be useful in helping older adults to make better credibility judgments. Keywords: Web credibility, cognitive aging, Elaboration Likelihood Model Introduction Because it is difficult to control the quality of the massive amount of online health information, many argue that credibility judgment should be taken as an indispensable component of online health information consumption, since health advice acquired from unreliable sources can be hazardous, or even life threatening. This issue becomes more prominent as studies have shown that, unlike other routine online activities such as reading news, users often do not have a trusted Web portal in mind when seeking for health related information. Instead, they often rely on search engines to solve their medical problems, and may bypass the main page and encounter information from untrusted sources (Eysenbach, 2007). A better understanding of the factors that influence credibility judgment will greatly enhance the safety and effectiveness of online health information consumption by the public. Among the increasing number of e-health consumers, older adults constitute a notable group, possibly because of their naturally higher need for health information. Research has shown that, compared to younger adults, older adults tend to exhibit distinctive behavior and performance in terms of searching, evaluating, and comprehending Web information (Chin & Fu, 2010; Hanson, 2009). The age differences, according to these studies, could be attributed to some unique characteristics of older adults, such as declined cognitive ability and inadequate experience with information technology. Despite its importance, there is a general lack of research studying age differences in credibility judgment of online information. To the best of our knowledge, there is still no research aiming at unpacking how age differences, cognitive abilities, Internet Related Work Many research studies on Web credibility have assumed some forms of the dual processing model of persuasive communications (e.g., Metzger, 2007) such as the Elaboration Likelihood Model (ELM, Petty & Cacioppo, 1986). When applying the ELM to Web credibility, individual’s attitude formation could be explained as they encounter two distinctive types of cues: (1) content cues are associated with the content/argument of Web information, which requires systematic, deliberative processing, and (2) contextual cues may be associated with the surface features of the Websites (e.g., interface design, information source, etc), which can be processed in a heuristic way by relying on practical rules or experience (Petty & Cacioppo, 1986). How cues from these two sources interact and impact users’ credibility judgment is an interesting question since users may often receive cues that contradict each other. For example, one study showed that credibility features of healthcare Website have only small correlation with the accuracy of information it provided (Heinke et al., 2002), which implies that apparently credible Website may not necessarily provide reliable health information. Since the processing of content cues tends to be more cognitively demanding, studies have found that users tended to process them by heuristic processing (Hilligoss & Rieh, 2008;.Sillence et al., 2007). However, there existed mixed results regarding the effects of specific contextual cues on users’ credibility assessment. While most studies showed that notably better design appearances contributed