New approaches can yield new results
Industrial and systems engineers at North Carolina State University examine public health systems
The Engineering the North Carolina Health Alert Network project (see all 4 projects) will document and describe the processes and resources of the North Carolina Health Alert Network (NC HAN) with the goal of understanding and quantifying the response capacity and suggesting ways to ensure efficient, effective response to public health threats.
The research employs systems engineering, a field that originated in the 1930s. As engineering projects became more complex, the need emerged to use an inter-disciplinary approach to understand the system as a whole rather than the sum of discreet parts. In simple language, industrial engineers figure out how to do things better. They look at decision making as well as technical processes. Without the field of systems engineering, we could not have made it to the moon or have cell phones!
The field of systems engineering is a promising integrator of diverse disciplines to be applied to the complex systems involved in public health preparedness. While some researchers have begun to apply this field to the study of health care systems, the NC HAN project will break new ground by applying sophisticated tools to a public health system.
We can see the potential importance of systems research today as the public health infrastructure has become far more complex over the past few years.
The diagram below, called a skeleton, shows the first step in the process of modeling the communication flows and decision making in the NC HAN system. Starting from rough sketches on a white board, the team will create a sophisticated computer model representing the human decision making that occurs in an emergency situation such as an Escherichia coli outbreak, industrial plant explosion, wild fire, flood, or terrorist threat.
The technique, called Value Stream Mapping, shows the big picture of how things are connected and interdependent and focuses on the value of each action to achieve the desired result. The purpose is to conduct "what-if" scenarios and find inefficiencies in the system.
This is an opportunity to apply our tools to a new field -- public health emergency preparedness.
Dr. Julie Ivy
Dr. Julie Ivy leads the team of faculty and students at North Carolina State University. Liaisons at the North Carolina Division of Public Health’s Department of Information Technology (Larry Forrister and Ellen Zimmerman) and Communicable Disease Branch (Jean-Marie Maillard) help the engineers understand how the Health Alert Network functions.
Dr. Edward Baker, co-investigator for this project, provides an invaluable perspective with his experience as assistant surgeon general at the Centers for Disease Control and Prevention when federal funding was awarded to develop the national Health Alert Network after the terrorist attacks in 2001. This funding was part of an effort to strengthen the public health infrastructure to respond to a full range of threats.
The team is asking questions about NC HAN that include:
- How do decision makers currently use NC HAN?
- What are the characteristics of the types and distribution of alerts (e.g., by level of severity, location, affected area, notification area)?
- How can we quantify and characterize the impact of NC HAN in terms of increased response capacity?
- How do we define "value" in terms of NC HAN's impact (e.g., time saved, costs reduced, convenience, accuracy of the information, efficiency of the alerting process)?
To start to answer these questions, the team will look at the E. coli outbreak at the 2004 North Carolina State Fair as a case study. In one of the largest petting zoo outbreaks of E. coli to date, NC HAN was used to notify all North Carolina health departments since the approximately 800,000 fair visitors came from all over the state. After the alert, 45 case patients and 188 controls were enrolled into an epidemiologic case-control study.
While the focus of this project is on North Carolina’s health alerting system, we hope that this research will be of interest to public health around the country, as the national HAN system provides vital health information and infrastructure at state and local levels.