Health Systems

, Volume 5, Issue 2, pp 140–148 | Cite as

Quantifying patient flow and utilization with patient flow pathway and diagnosis of an emergency department in Singapore

  • Fanwen MengEmail author
  • Chee Kheong Ooi
  • Christopher Kok Keng Soh
  • Kiok Liang Teow
  • Palvannan Kannapiran
Original Article


Patient treatment and care in emergency departments (ED) is complex because of differences in patients’ acuity, co-morbidities and diagnoses. This paper aims to study how different diagnosis groups impact the utilization, which we estimate from patients’ touch points, of various functional areas at ED. We first mapped patient flow pathways across key functional areas in ED, and illustrated them using a network graph. We measured the utilization of these key areas and stratified them by diagnosis groups. The contribution of each diagnosis group to the area utilization was then estimated. A mathematical model was developed to perform impact analysis on the demand based on the utilization pattern. In particular, we estimated the changes in patients’ touch points in the key areas with the changes to the volumes of different diagnosis groups. The study showed that different diagnosis groups have different impact on the demand at the functional areas. In particular, patients with the diagnosis ‘Symptoms, signs and ill-defined conditions’ had the highest impact on the demand in almost all ED areas. The diagnosis ‘Acute respiratory infections’ appeared to have higher impact on the demand in the areas of Fever and Fever Observation.


emergency department utilization diagnosis patient flow pathway impact analysis 



The authors are grateful to the anonymous referees for their careful readings and suggestions, which helped to improve the presentation of the paper. We would also like to thank Kenneth Lim Teck Kiat from Health Services & Outcomes Research, National Healthcare Group Singapore for assisting with the manuscript revision.


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Copyright information

© Operational Research Society Ltd 2015

Authors and Affiliations

  • Fanwen Meng
    • 1
    Email author
  • Chee Kheong Ooi
    • 1
    • 2
  • Christopher Kok Keng Soh
    • 1
    • 2
  • Kiok Liang Teow
    • 1
  • Palvannan Kannapiran
    • 1
  1. 1.Department of Health Services and Outcomes ResearchNational Healthcare GroupSingaporeSingapore
  2. 2.Department of Emergency MedicineSingapore

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