SIMULATION STUDIES OF A WIDE AREA HEALTH-CARE NETWORK

There is an increasing number of efforts to install wide area health c are networks. Some of these networks are being built to support severa l applications over a wide user base consisting primarily of medical p ractices, hospitals, pharmacies, medical laboratories, payors, and sup pliers. Although on-line, multi-media telecommunication is desirable f or some purposes such as cardiac monitoring, store-and-forward messagi ng is adequate for many common, high-volume applications. Laboratory t est results and payment claims, for example, can be distributed using electronic messaging networks. Several network prototypes have been co nstructed to determine the technical problems and to assess the effect iveness of electronic messaging in wide area health care networks. Our project, Health Link, developed prototype software that was able to u se the public switched telephone network to exchange messages automati cally, reliably and securely. The network could be configured to accom modate the many different traffic patterns and cost constraints of its users.Discrete event simulations were performed on several network mo dels. Canonical star and mesh networks, that were composed of nodes op erating at steady state under equal loads, were modeled. Both topologi es were found to support the throughput of a generic wide area health care network. The mean message delivery time of the mesh network was f ound to be less than that of the star network. Further simulations wer e conducted for a realistic large-scale health care network consisting of 1,553 doctors, 26 hospitals, four medical labs, one provincial lab and one insurer. Two network topologies were investigated: one using predominantly peer-to-peer communication, the other using client-serve r communication. The client-server model was less expensive to operate but also less responsive to message priorities.