Staff Assignment in Emergency Department Considering Service Time

Document Type : Research Paper


1 Department of Industrial Engineering, Islamic Azad University, Bonab Branch, Bonab, Iran

2 Department of Industrial Engineering, Islamic Azad University, Tabriz branch, Tabriz, Iran

3 Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul, Turkey



This paper designs an optimization model for the emergency department of a hospital, considering related costs, nursing staff satisfaction, and waiting time for several diseases concerning the number of staff in each shift. This study's primary purpose is to minimize the related costs, maximize nursing staff satisfaction, and allocate nursing staff to working shifts in the emergency department. In the first stage, a simulation model is constructed based on the emergency department's status with ARENA 14 software. Then, the model is investigated under three different scenarios. In the second stage, mixed-integer programming is proposed to minimize the costs, nursing staff satisfaction and optimally allocate nurses to various shifts. Furthermore, the generalized center method is used to solve the model by converting the multi-objective model to a single-objective one. In Tabriz, Iran, Imam Reza hospital is considered our case study investigated by simulation and MIP models. Finally, the results of simulation and mathematical models demonstrate that six new nurses should be added to the emergency department.


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