A computer-based flowcharting system for clinical protocols

In medicine, scientific and technological developments for investigation and treatment are proceeding at an ever increasing rate. Protocols for patient management are becoming ever more complicated. Rational design and scientific evaluation of protocols requires precise documentation. We propose a notation based on a series of simple flowcharts which describe procedures in increasing detail. Each step in a flowchart is justified by a reasoned argument, possibly including reference to published articles. General correctness requirements of a protocol include, for example, conformity with known indications and contraindications for investigations and treatments. These correctness requirements can be specified declaratively in mathematical logic and justified by reasoned argument. This makes the correspondence between a protocol and its scientific foundation even more explicit. Flowcharts of this nature are more easily created and modified using a personal computer. Furthermore, use of the computer enables a protocol to be checked automatically against its specification for more rapid identification of errors during development and maintenance of the protocol. We present the structured design of our flowcharting system in the 'Z' specification language, and we examine the practicality of our approach by means of a case study; the management of infertility. Our flowcharting system may also have application outside medicine where it is necessary to describe formal protocols for complex procedures.