A tutorial on discrete-event simulation for health policy design and decision making: optimizing pediatric ultrasound screening for hip dysplasia as an illustration.

BACKGROUND: It is increasingly recognized that healthcare is a complex system with limited resources and many interacting sources of both positive and negative feedback. Discrete-event simulation (DES) is a tool that readily accommodates questions of capacity planning, throughput management and interacting resources. As a result the use of DES in informing healthcare decision making is increasing. However, understanding when and how to build a DES model and use it for policy making is not yet a common knowledge.

METHODS: The steps in building a DES model will be demonstrated using a real-world example, i.e., pediatric ultrasound screening for hip dysplasia. The main components of a DES model such as entities, resources and queues will be introduced and we will examine questions such as referral schedule, number of ultrasound machines and type of screeners and how these entities interact. Finally a review of the statistical techniques appropriate to DES will be provided.

CONCLUSION: Discrete-event simulation is a valuable tool in the policymakers armentarium. It can be used effectively to analyze and understand complex healthcare systems and policy problems such as population screening.