Stochastic Systems

On patient flow in hospitals: A data-based queueing-science perspective

Mor Armony, Shlomo Israelit, Avishai Mandelbaum, Yariv N. Marmor, Yulia Tseytlin, and Galit B. Yom-Tov

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Hospitals are complex systems with essential societal benefits and huge mounting costs. These costs are exacerbated by inefficiencies in hospital processes, which are often manifested by congestion and long delays in patient care. Thus, a queueing-network view of patient flow in hospitals is natural for studying and improving its performance. The goal of our research is to explore patient flow data through the lens of a queueing scientist. The means is exploratory data analysis (EDA) in a large Israeli hospital, which reveals important features that are not readily explainable by existing models.

Questions raised by our EDA include: Can a simple (parsimonious) queueing model usefully capture the complex operational reality of the Emergency Department (ED)? What time scales and operational regimes are relevant for modeling patient length of stay in the Internal Wards (IWs)? How do protocols of patient transfer between the ED and the IWs influence patient delay, workload division and fairness? EDA also underscores the importance of an integrative view of hospital units by, for example, relating ED bottlenecks to IW physician protocols. The significance of such questions and our related findings raise the need for novel queueing models and theory, which we present here as research opportunities.

Hospital data, and specifically patient flow data at the level of the individual patient, is increasingly collected but is typically confidential and/or proprietary. We have been fortunate to partner with a hospital that allowed us to open up its data for everyone to access. This enables reproducibility of our findings, through a user-friendly platform that is accessible via the Technion SEELab.

Article information

Stoch. Syst., Volume 5, Number 1 (2015), 146-194.

Received: June 2014
First available in Project Euclid: 23 December 2015

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Zentralblatt MATH identifier

Queueing models queueing networks healthcare patient flow EDA emergency departments hospital wards event logs


Armony, Mor; Israelit, Shlomo; Mandelbaum, Avishai; Marmor, Yariv N.; Tseytlin, Yulia; Yom-Tov, Galit B. On patient flow in hospitals: A data-based queueing-science perspective. Stoch. Syst. 5 (2015), no. 1, 146--194. doi:10.1214/14-SSY153.

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