Analysis of emergency department waiting lines

  • Urška Močnik Zdravstveni dom Idrija
  • Mirko Gradišar Katedra za poslovno informatiko in logistiko, Ekonomska fakulteta, Univerza v Ljubljani
  • Luka Tomat Katedra za poslovno informatiko in logistiko, Ekonomska fakulteta, Univerza v Ljubljani
Keywords: emergency department, decision-making, waiting lines, simulation, feasibility study


Background: Steady increase in the numbers of patients seeking medical assistance has recently been observed at the emergency department of the health center under study. This has led to increases in waiting times for patients. The management of the health center has been considering to implement certain measures to remedy this situation. One proposed solution is to add an additional physician to the emergency department. A computer model was constructed to simulate waiting lines and analyze the economic feasibility of employing an additional physician.

Aim: This paper analyzes the waiting lines at the emergency department and performs an economic feasibility study to determine whether adding an additional physician to the department would be economically justified.

Methods: Data about waiting times at the emergency department were collected to study the situation. For each patient, the arrival time at the waiting room and the starting and ending times of the examination were registered. The data were collected from 13 June 2011 to 25 September 2011. The sample included data on 65 nightly standbys, nine standbys on Saturdays, and 16 standbys on Sundays. Due to incomplete entries, data for nine weekly standbys and six Saturday standbys were excluded from the sample. Based on the data collected, we calculated the waiting and examination times per patient, average number of patients, average waiting time, average examination time, share of active standby teams in total standby time, and number of patients in different time periods. The study involved 1,039 patients. Using a synthesis method, we designed a computer model of waiting lines and economic feasibility. The model was validated using comparative analysis. A what-if analysis was performed using various computer simulations with various scenarios to consider the outcomes of decision alternatives. We applied economic analysis to select the best possible solution.

Results: The research results show that emergency department teams face overcrowding at certain periods. This is particularly challenging for employees performing 24-hour standbys, when they are working at the limit of their capacity. The results show that the total cost of waiting lines with two physicians is higher in all cases. The introduction of an additional channel or employing an additional physician increases the total cost by 35 to 50 %. Employing an additional physician is therefore not economically justified.

Conclusion: This study showed how a computer model can be used to improve the information basis for decision-making in healthcare organization management. Based on quantitative data obtained by using a model with alternative scenarios, we developed an economic analysis of alternatives and made a decision. The cost analysis of potentially employing an additional physician showed that the cost would exceed the benefits obtained in all scenarios analyzed. The proposed decision-support method can be implemented at a very low cost in all healthcare organizations dealing with similar problems.


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How to Cite
Močnik U, Gradišar M, Tomat L. Analysis of emergency department waiting lines. ZdravVestn [Internet]. 1 [cited 17Jan.2019];83(9). Available from:
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