Performance of SAPS II according to ICU length of stay: Protocol for an observational study

Severity scores, including the Simplified Acute Physiology Score (SAPS) II, are widely used in the intensive care unit (ICU) to predict mortality outcomes using data from ICU admission or shortly hereafter. For patients with longer ICU length of stay (LOS), the predictive performance of admission‐based severity scores may deteriorate compared to patients with shorter ICU LOS. This protocol and statistical analysis plan outlines a study that will assess the influence of ICU LOS on the performance of SAPS II for predicting 90‐day post‐ICU mortality.

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