Architecture for a Web-based clinical information system that keeps the design open and the access closed

We are developing the Patient Clinical Information System (PatCIS) project at Columbia-Presbyterian Medical Center to provide patients with access to health information, including their own medical records (permitting them to contribute selected aspects to the record), educational materials and automated decision support. The architecture of the system allows for multiple, independent components which make use of central services for managing security and usage logging functions. The design accommodates a variety of data entry, data display and decision support tools and provides facilities for tracking system usage and questionnaires. The user interface minimizes hypertext-related disorientation and cognitive overload; our success in this regard is the subject of on-going evaluation.