Pathways of coronary care—a computer-simulation model of the potential for health gain

A computer-simulation model of the need for cardiology services is described. The model simulates the potential for health gain, in terms of a fall in mortality, determining the effect of alterations in prevention and treatment rates. The model was initially developed from a pathways-of-care flow chart, which originated from a working group consisting of a consultant cardiac surgeon, cardiologists, and public-health physicians, together with statisticians and an operational-research analyst. The original purpose of the model was as a communication tool, to help nonclinicians to have a better understanding of how and why doctors work as they do, but it has since been developed for use in setting and meeting health targets. It enables quantification of the effects of changing different combinations of key variables over time. It is designed to answer 'what if?' questions of the type 'What would the effect of a 10% reduction in the incidence of angina be on the number of deaths, angiograms, angioplasties, and coronary-artery bypass grafts. The model has been made available in a form which only requires a Lotus 123 spreadsheet package to enable it to run, and it is designed to be easy to use with the assistance of simple two-key commands throughout. The model has been used by district health authorities to calculate the response required in their own local areas to achieve targets for the year 2000.