A Think-Aloud Study to Understand Factors Affecting Online Health Search

The majority of US Internet users have searched the internet for health-related information. When people conduct these health searches, searching for information about medical treatments is among the more common reasons. While being a convenient and fast method to collect information, when used by people for health search, search engines can be biased toward results saying treatments are helpful, regardless of the truth. The presence of incorrect information in search results may potentially cause harm, especially if people believe what they read without further research or professional medical advice. In this paper, we aim to better understand the decision making process of determining the efficacy of medical treatments using search result pages. We conducted a think-aloud study in order to gain insights on strategies people use during online search for health related topics. We found that, even when participants are careful and focused on the task, biased search engine results can significantly influence people to make decisions consistent with the bias. The chief reason biased search engines results were able to influence participants is that participants often considered what the majority of the search results stated as part of their decision-making. We also found that participants looked for indications of authoritativeness and quality when evaluating online content. While rank bias and a bias towards wanting treatments to be helpful has been found in prior studies, our participants did not reveal these biases as part of their spoken thoughts. Our results imply that more attention should be paid to search engines' biases given people's bias towards accepting the most common answer in the results as the correct answer. When search results are biased toward incorrect results for health-related searches, dire consequences may be the result.