An intelligent terminal for access to a medical data base

Abstract

Very powerful data base management systems (DBMS) now exist which allow medical personnel access to patient record data bases. DBMSs make it easy to retrieve either complete or abbreviated records of patients with similar characteristics. In addition, statistics on data base records are immediately accessible. However, the price of this power is a large computer with the inherent problems of access, response time, and reliability. If a general purpose, time-shared computer is used to get this power, the response time to a request can be either rapid or slow, depending upon loading by other uses. Furthermore, if the computer is accessed via dial-up telephone lines, there is competition with other users for telephone ports. If either the DBMS or the host machine is replaced, the medical users, who are typically not sophisticated in computer usage, are forced to learn the new system. Microcomputers, because of their low cost and adaptability, lend themselves to a solution of these problems. A microprocessor-based intelligent terminal has been designed and implemented at the USAF School of Aerospace Medicine to provide a transparent interface between the user and his data base. The intelligent terminal system includes multiple microprocessors, floppy disks, a CRT terminal, and a printer. Users interact with the system at the CRT terminal using menu selection (framing). The system translates the menu selections into the query language of the DBMS and handles all actual communication with the DBMS and its host computer, including telephone dialing and sign on procedures, as well as the actual data base query and response. Retrieved information is stored locally for CRT display, hard copy production, and/or permanent retention. Microprocessor-based communication units provide security for sensitive medical data through encryption/decryption algorithms and high reliability error detection transmission schemes. Highly modular software design permits adaptation to a different DBMS and/or host computer with only minor localized software changes. Importantly, this portability is completely transparent to system users. Although the terminal system is independent of the host computer and its DBMS, it has been linked to a UNIVAC 1108 computer supporting MRIs SYSTEM 2000 DBMS.