Murat M. Gunal

Discrete event simulation for performance modelling in health care: a review of the literature

Discrete Event Simulation (DES) has been widely used in modelling health-care systems for many years and a simple citation analysis shows that the number of papers published has increased markedly since 2004. Over the last 30 years several significant reviews of DES papers have been published and we build on these to focus on the most recent era, with an interest in performance modelling within hospitals. As there are few papers that propose or illustrate general approaches, we classify papers according to the areas of application evident in the literature, discussing the apparent lack of genericity. There is considerable diversity in the objectives of reported studies and in the consequent level of detail: We discuss why specificity dominates and why more generic approaches are rare.

Understanding accident and emergency department performance using simulation

As part of a larger project examining the effect of performance targets on UK hospitals, we present a simulation of an Accident and Emergency (A&E) Department. Performance targets are an important part of the National Health Service (NHS) performance assessment regime in the UK. Pressures on A&Es force the medical staff to take actions meeting these targets with limited resources. We used simulation modelling to help understand the factors affecting this performance. We utilized real data from patient admission system of an A&E and presented some data analysis. Our particular focuses are the multitasking behaviour and experience level of medical staff, both of which affect A&E performance. This performance affects, in turn, the overall performance of the hospital of which it is part

Interconnected DES models of emergency, outpatient, and inpatient departments of a hospital

National Health Service (NHS) performance targets in England have put pressure on hospital management to reduce waiting times. The stochastic nature of emergency patient arrivals creates problems for capacity planning for elective patients. We present a whole hospital model which can be used at policy level to investigate cause and effect relations, such as effects of increased emergency arrival volumes on elective waiting times. A typical general hospital can be abstracted in three main units; Accident and Emergency (A&E) department, outpatient clinics, and inpatient units. In real life these units are coupled and share hospital resources. We developed three discrete event simulation (DES) models for each unit to form a whole hospital DES model. We present our models conceptually and our main discussion is on the level of detail in these three models.

DGHPSIM:: Generic simulation of hospital performance

The British National Health Service (NHS) has a performance management framework that aims to guarantee short waiting times for patients by including mandatory targets for hospitals. DGHPSim is a suite of four components that simulates the activities of an NHS general hospital to show the effect of different policies on waiting times in these hospitals. DGHPSim has a generic structure that is used to simulate a particular hospital by employing data appropriate to that hospital from available data sets. Two of the components of DGHPSim, the accident and emergency simulator and the outpatient simulator, may be used independently as stand-alone simulators of these hospital functions. The DGHPSim suite incorporates a novel way of simulating the multitasking behavior of clinicians and uses transition matrices, extracted from standard datasets, to represent the states through which patients pass and the wards in which they may be treated. As a whole, the DGHPSim suite may be used to investigate improvement options before their implementation or to investigate how a hospital has improved its performance. We show how DGHPSim is used to investigate reported performance improvements in an English general hospital.

Simulation modelling for performance measurement in healthcare

Discrete event simulation is widely used to model healthcare systems with a view to their improvement. Most applications focus on discrete aspects of healthcare, such as accident and emergency rooms or outpatient clinics. However, despite this success with simulation at an operational level, there are no reported uses of discrete event simulation for the development and improvement of health policy. We describe the development of such a policy-oriented model, aimed at improving performance assessment in the UK National Health Service

DGHPSim: supporting smart thinking to improve hospital performance

DGHPSim is a suite of discrete event simulation models that enable managers and clinicians to investigate improvement scenarios for UK general hospitals. The models were developed in Micro Saint Sharp and are configured using hospital data and nationally available health episode statistics. The models can be separately but function best as a single, overall system model that allow users to develop understanding of the interaction effects of possible changes. An example of the use of DGHPSim is given, using UK NHS data, demonstrating how it can be used to investigate improvement options whilst keeping an eye on side effects.

Improving police control rooms using simulation

Police command and control centres are the main point of contact for the public who require help. Like other areas of UK public services, police forces are set targets for their performance. Some of these targets relate to the speed at which they respond to calls for assistance from the public. In this paper we share our experience in improving the performance of command and control centres of a UK Police Force; a project which started as a classical simulation exercise and ended up with a significant reorganization in a UK Police Force.