Health Care Management Science

, Volume 7, Issue 2, pp 89–96 | Cite as

Analysis of the Expenses Linked to Hospital Stays: How to Detect Outliers

  • C. Beguin
  • L. Simar


When hospital financing depends on a budget which in turn depends on the pathologies being treated, it is necessary to detect hospital stays which show discrepancies between the resources they consume and the medical characteristics they present. Deterministic nonparametric frontier models are used to rank hospital stays according to their expenses taking into account the severity of the patients' conditions. As these models are very sensitive to the extreme stays, a robust frontier model, the order-m frontier is used. The too-efficient stays are highlighted and described. The mean expenses are estimated after excluding too-efficient and inefficient stays. This mean is higher than the mean estimated by using classical trimming rules.

deterministic nonparametric frontier models free disposal hull outliers 


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Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  1. 1.Centre d'Informatique MédicaleCliniques Universitaires Saint Luc, Université Catholique de LouvainBelgium
  2. 2.Institut de Statistique, Université Catholique de LouvainBelgium

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