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Predictive scoring systems in the intensive care unit

Mark A Kelley, MD, MACP
Section Editor
Scott Manaker, MD, PhD
Deputy Editor
Geraldine Finlay, MD


Predictive scoring systems are measures of disease severity that are used to predict outcomes, typically mortality, of patients in the intensive care unit (ICU). Such measurements are helpful for standardizing research and comparing the quality of patient care across ICUs. The common validated predictive scoring systems and their uses in the ICU are described in this topic.


Scoring systems are typically developed using prospectively collected data from a large number of patients from several intensive care units (ICUs):

Data include previous and current clinical health information (eg, comorbidities, admission diagnosis) as well as physiologic and laboratory data (eg, mean arterial pressure, partial pressure of oxygen). (See 'Data collection' below.)

The data are used to determine a numerical severity of illness score. (See 'Calculations' below.)

The score, in turn, determines outcomes at hospital discharge including mortality, and sometimes length of stay. (See 'Outcome measures' below.)

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Literature review current through: Nov 2017. | This topic last updated: Jan 27, 2017.
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