Ongoing research into the design and development of ClinicalTrials.gov and other health information systems must consider the needs, experience, and medical knowledge of a diverse audience. Research questions currently being investigated include:

• Are consumers able to find the information they need?
• Do consumers understand the information they find?
• What tools may be developed to assist consumers overcome barriers to finding and understanding information?
• How are consumers using ClinicalTrials.gov?
• What is the best way to display clinical research information?
• How can advanced computer, information science, and Web technologies be used to enhance and support consumer health information systems?

Results from health information systems research are used to develop new tools that will improve ClinicalTrials.gov, contribute insights into consumer health information seeking behavior and needs, and provide guidelines for developing consumer health information systems.