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Intensive Care Medicine

, Volume 36, Issue 7, pp 1207–1212 | Cite as

Characterizing the risk profiles of intensive care units

  • Rui P. Moreno
  • Helene Hochrieser
  • Barbara Metnitz
  • Peter Bauer
  • Philipp G. H. Metnitz
Original

Abstract

Objective

To develop a new method to evaluate the performance of individual ICUs through the calculation and visualisation of risk profiles.

Methods

The study included 102,561 patients consecutively admitted to 77 ICUs in Austria. We customized the function which predicts hospital mortality (using SAPS II) for each ICU. We then compared the risks of hospital mortality resulting from this function with the risks which would be obtained using the original function. The derived risk ratio was then plotted together with point-wise confidence intervals in order to visualise the individual risk profile of each ICU over the whole spectrum of expected hospital mortality.

Main measurements and results

We calculated risk profiles for all ICUs in the ASDI data set according to the proposed method. We show examples how the clinical performance of ICUs may depend on the severity of illness of their patients. Both the distribution of the Hosmer–Lemeshow goodness-of-fit test statistics and the histogram of the corresponding P values demonstrated a good fit of the individual risk models.

Conclusions

Our risk profile model makes it possible to evaluate ICUs on the basis of the specific risk for patients to die compared to a reference sample over the whole spectrum of hospital mortality. Thus, ICUs at different levels of severity of illness can be directly compared, giving a clear advantage over the use of the conventional single point estimate of the overall observed-to-expected mortality ratio.

Keywords

Risk adjustment Risk stratification Outcome Intensive care Severity of illness 

Notes

Acknowledgments

The study was supported by the Austrian Centre for Documentation and Quality Assurance in Intensive Care Medicine (ASDI). Our special thanks to the participants from all the ICUs that participated in the project.

Supplementary material

134_2010_1852_MOESM1_ESM.doc (4 mb)
Supplementary material 1 (DOC 4126 kb)

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Copyright information

© Copyright jointly held by Springer and ESICM 2010

Authors and Affiliations

  • Rui P. Moreno
    • 1
  • Helene Hochrieser
    • 2
  • Barbara Metnitz
    • 2
  • Peter Bauer
    • 2
  • Philipp G. H. Metnitz
    • 3
  1. 1.Unidade de Cuidados Intensivos PolivalenteHospital de Santo António dos Capuchos, Centro Hospitalar de Lisboa Central, E.P.E.LisbonPortugal
  2. 2.Section for Medical StatisticsMedical University of ViennaViennaAustria
  3. 3.Department of Anesthesiology and General Intensive CareMedical University of ViennaViennaAustria

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