Special considerations for WEB-based clinical database applications

The Hospital Information System at the University of Missouri-Columbia Veterinary Medical Teaching Hospital is implementing a web-based interface to the existing Hospital Information System. The "stateless" nature of HTML forms introduces a number of special considerations that, though not immediately obvious, nevertheless apply to any multi-user database application. Problems including identifying sessions and users, dealing with abandoned sessions or use of the "Back" arrow on the browser, record locking across multiple forms, state variables, and flow through "utility" forms. General solutions to each of these problems have been devised and are presented here.