Believing in Expertise: How Authors’ Credentials and Language Use Influence the Credibility of Online Health Information

Today, many people use the Internet to seek health advice. This study examines how an author's expertise is established and how this affects the credibility of his or her online health information. In a 2 (authors' credentials: medical vs. nonmedical) × 2 (authors' language use: technical vs. every day) within-subjects design, 127 study participants, or "seekers," judged authors' expertise, benevolence, and integrity as well as the credibility of their medical statements. In addition, we assessed seekers' awareness of their own knowledge and behavior. Results revealed that users consciously rewarded authors' credentials and subconsciously punished technical language. Seekers were keenly aware of authors' credentials and perceived authors with medical credentials to have a higher level of expertise and their information to be more credible. Technical language use negatively affected authors' integrity and the credibility of their health information, despite seekers being unaware of it. Practical implications for health communication and implications for future research are outlined.