iMPACT3: online tools for development of web sites for the study of Patients' preferences and utilities

Preferences for health outcomes, often called utilities, are numeric measurements of the patients' opinions about overall quality of life with a disease or a health condition. These measurements are used in economic studies (cost effectiveness analysis) as weights for life years (so called Quality adjusted life years or QALYs), in development of guidelines for clinical care (again as quality weights for life years), and to help identify the best treatment alternative for individual patients through application of decision analysis. iMPACT3 (Internet Multimedia Preference Assessor Construction Tool) is a free publicly accessible web site that helps researchers design experimental protocols for measurement of utilities. When the researcher is finished with his or her design, iMPACT3 generates a set of HTML files that use Javascript to implement the protocol. iMPACT3 then downloads those to the researcher's computer, where they can be used in a stand alone fashion to collect data from patients in a clinic or published on the web. We describe and discuss computer approaches for measurement of utilities and their applications in healthcare. We then discuss the design of iMPACT3 and approaches for automatic generation of web sites for data collection in clinical studies.