Healthcare technologies are evolving from a practitioner-centric model to a patient-centric model due to the increasing need for technology that directly serves healthcare consumers, including healthy people and patients. Personal health information management (PHIM) technology is one of the technologies designed to enhance an individual's ability to manage their personal health information. Healthcare consumers struggle with common challenges of PHIM, but the acceptance of PHIM technology, such as personal health record (PHR) systems, has not yet become widespread. This thesis employed mixed methods to identify and understand the factors that influence healthcare consumer acceptance and usage of PHIM technologies, and to improve the user interface design of PHIM technology from consumers' perspectives. Both quantitative and qualitative methods were applied including 1) questionnaire surveys to identify and measure factors influencing the acceptance and usage of PHIM technologies; 2) interviews for a deeper understanding the critical factors determined from the questionnaire survey, and to explore the solution to improve the user interface from consumers' perspective; and 3) controlled experiments to validate the important factors and the design guidelines determined through the questionnaire survey and interview studies. The research results indicated an overall low usage rate among PHR systems (about 10%). Six factors were identified to be associated with use "intention". "Perceived usefulness" and "health information understandability" explained 26% of the variance of the "use intention" (R[superscript 2]=0.26, p<0.001) in the regression model. Additionally, "use intention" was found to be associated with "personalization" (r = 0.56, p<0.001), "patient-clinician communication" (r = 0.50, p<0.001), "social influence" (r = 0.54, p<0.001), and "willingness to share" (r = 0.52, p<0.001). User interface design guidelines were proposed and validated regarding "perceived usefulness", "health information understandability", "personalization", and "patient-clinician communication". Future work can involve larger-scale studies testing more tailored design features to compensate for the evolving technology expectations of healthcare consumers. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]