Health Care Management Science

, Volume 22, Issue 1, pp 85–105 | Cite as

Classification of hospital admissions into emergency and elective care: a machine learning approach

  • Jonas Krämer
  • Jonas SchreyöggEmail author
  • Reinhard Busse


Rising admissions from emergency departments (EDs) to hospitals are a primary concern for many healthcare systems. The issue of how to differentiate urgent admissions from non-urgent or even elective admissions is crucial. We aim to develop a model for classifying inpatient admissions based on a patient’s primary diagnosis as either emergency care or elective care and predicting urgency as a numerical value. We use supervised machine learning techniques and train the model with physician-expert judgments. Our model is accurate (96%) and has a high area under the ROC curve (>.99). We provide the first comprehensive classification and urgency categorization for inpatient emergency and elective care. This model assigns urgency values to every relevant diagnosis in the ICD catalog, and these values are easily applicable to existing hospital data. Our findings may provide a basis for policy makers to create incentives for hospitals to reduce the number of inappropriate ED admissions.


Emergency care Elective care Hospital Machine learning Classification Random forest 


Compliance with ethical standards

Conflict of interest

The authors have no conflicts of interest to declare.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2017

Authors and Affiliations

  • Jonas Krämer
    • 1
  • Jonas Schreyögg
    • 1
    Email author
  • Reinhard Busse
    • 2
  1. 1.Hamburg Center for Health EconomicsUniversität HamburgHamburgGermany
  2. 2.Department of Healthcare ManagementTechnische Universität BerlinBerlinGermany

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