What do patients search for when seeking clinical trial information online?

The Internet has become a common source for consumers to seek health information across a wide range of topics including searching for clinical trials. However, not much is known about what consumers search for in relation to clinical trials and how they formulate their search queries. In this study, we use log file data from TrialX.com, a consumer-centric website that provides clinical trial information to ascertain patterns in consumer queries. We analyzed semantic patterns in the queries by mapping query keywords to the UMLS Semantic Types and performed a manual evaluation of user paths. We found that the queries can be grouped into combinations of information needs related to condition, location and treatment. The results also suggested that the consumers using longer search queries with multiple Semantic Types are more likely to take action to participate in clinical trials. The study provides early insights that can be used to inform changes in website content and information display to improve clinical trials information seeking.