Experience of transferring an integrated hospital-administration system from a CODASYL data-base to a standard MUMPS file structure.

University College Hospital, a teaching hospital situated in Central London, has been using computers since 1964. Development of an integrated on-line hospital administration computer system was started in 1974. By mid 1977, the components of the system which had been implemented included a patient Master Index, Registration of new patients, Waiting Lists, Bed State, Out-patient Appointments, X-ray, Microbiology and Disease Index. The system was implemented using the Rank Xerox Data Systems (CODASYL based data-base management software, with the majority of applications running on a terminal network supported by transaction processing programs. The experience gained during three years of using such a system is reviewed, with particular emphasis on the ways in which the system matched up in practice to the expected benefits of data-base management facilities. In early 1977, it was decided to replace the Rank Xerox mainframe with a minicomputer which was considered to be a more cost-effective solution to the hospital's computing requirements. The machine selected a PDP 11-70, is running the Digital Equipment Corporation's implementation of Standard MUMPS, an interpretive language developed in a hospital environment, with its own file management software. The decisions which were made in redesigning the existing computer systems for the new machine are discussed. The progress made to date in the transfer of applications from the mainframe to the mini is reviewed, and some of the features of the software available on each machine and its suitability for the implementation of on-line data management and retrieval systems are compared.