Document Type

Conference Paper

Publication Date


Publication Title

Selected Papers and Presentations Presented at MODSIM World 2010 Conference and Expo


1-18 pp.

Conference Name

MODSIM World 2010 Conference Expo, October 13-15, 2010, Hampton, Virginia


Ambulatory health care needs within the United States are served by a wide range of hospitals, clinics, and private practices. The Emergency Department (ED) functions as an important point of supply for ambulatory healthcare services. Growth in our aging populations as well as changes stemming from broader healthcare reform are expected to continue trend in congestion and increasing demand for ED services. While congestion is, in part, a manifestation of unmatched demand, the state of the alignment between the demand for, and supply of, emergency department services affects quality of care and profitability. The central focus of this research is to provide an explanation of the salient factors at play within the dynamic demand-supply tensions within which ambulatory care is provided within an Emergency Department. A System Dynamics (SO) simulation model is used to capture the complexities among the intricate balance and conditional effects at play within the demand-supply emergency department environment. Conceptual clarification of the forces driving the elements within the system , quantifying these elements, and empirically capturing the interaction among these elements provides actionable knowledge for operational and strategic decision-making.


Work of the US Gov. Public Use Permitted. (no copyright)

Original Publication Citation

Diaz, R., Behr, J. G., & Tulpule, M. (2011). Ambulatory healthcare utilization in the United States: A system dynamics approach. Paper presented at the MODSIM World 2010 Conference and Expo, NASA Langley Research Center, Hampton, VA, United States.


0000-0002-8637-5967 (Diaz), 0000-0002-0472-3068 (Behr)