Proceedings of the 2016 Winter Simulation Conference T. M. K. Roeder, P. I. Frazier, R. Szechtman, E. Zhou, T. Huschka, and S. E. Chick, eds. NGOMSL SIMULATION MODEL IN AN EMERGENCY DEPARTMENT Nithin Parameshwara Jung Hyup Kim Wenbin Guo Kalyan S Pasupathy Department of Industrial and Manufacturing Systems Engineering University of Missouri E3437 Thomas & Lafferre Hall Columbia, MO 65211, USA Emergency Department Clinical Engineering Learning Lab Kern Center for the Science of Health Care Delivery Mayo Clinic 200 First Street SW Rochester, MN 55905, USA ABSTRACT Natural Goals Operators Methods and Selection Rules Language (NGOMSL) model of the clinical process in an Emergency Department (ED) was developed using Micro Saint Sharp. This model advanced our understanding of a care provider’s cognitive behavior in a dynamic ED environment. It also revealed the understanding of proximal workflow in the ED and the workload related to clinical processes. The benefits of this study are (a) improved understanding of the relevant form factors of the clinical process that contribute to a heavy workload in the ED and (b) prevention of potential errors caused by the workload. To understand the current ED workflow, hierarchical task analysis (HTA) charts were developed. The HTA charts were used to understand the detailed process mappings of nurses in the ED. Based on this multi-level analysis of the HTA charts, the NGOMSL simulation model was developed. 1 INTRODUCTION Patients mostly visit the emergency department (ED) to seek urgent care. The ED is the busiest and most unpredictable area in a hospital. Recently, most emergency departments have experienced dramatic increases in patient volume over the past decade. In 2015, a poll conducted by the American College of Emergency Physicians on 2,099 emergency physicians nationally showed that about 28% of the physicians surveyed saw significant increases in patient volume while 47% saw slight increases (Ungar and O'Donnell 2015). Owing to this overwhelming pressure to provide effective and complete patient care in a short period, the ED workflow is usually encapsulated by a great deal of complexity (Brailsford et al. 2004). The medical staff members in the ED have to provide efficient, consistent, and cost-effective care while attempting to keep patients satisfied and avoid malpractice risks. The incompatibility of demand and supply for service in the ED affects the emergency medical staff members’ capability to provide effective patient care. Although effective patient care is crucial for making a more patient-oriented healthcare system, nurses are unable to make this transition because of an unbalanced and excessive workload attributed to patient care and processing of health records in the ED. One of the factors responsible for this notable increase in workload is the electronic medical record (EMR) system. The impact of EMR has received a lot of attention in recent years because the EMR promises potential benefits to the practice of medical care in the ED. However, electronic recording process requires more time to complete documentation as compared to paper records (Perry et al. 2013). In addition, the EMR with information system is the cause for increasing 978-1-5090-4486-3/16/$31.00 ©2016 IEEE 1938