The ability of the National Early Warning Score (NEWS) to discriminate patients at risk of early cardiac arrest, unanticipated intensive care unit admission, and death.

Abstract

Early warning scores (EWS) are recommended as part of the early recognition and response to patient deterioration. The Royal College of Physicians recommends the use of a National Early Warning Score (NEWS) for the routine clinical assessment of all adult patients. We tested the ability of NEWS to discriminate patients at risk of cardiac arrest, unanticipated intensive care unit (ICU) admission or death within 24h of a NEWS value and compared its performance to that of 33 other EWSs currently in use, using the area under the receiver-operating characteristic (AUROC) curve and a large vital signs database (n=198,755 observation sets) collected from 35,585 consecutive, completed acute medical admissions. The AUROCs (95% CI) for NEWS for cardiac arrest, unanticipated ICU admission, death, and any of the outcomes, all within 24h, were 0.722 (0.685-0.759), 0.857 (0.847-0.868), 0.894 (0.887-0.902), and 0.873 (0.866-0.879), respectively. Similarly, the ranges of AUROCs (95% CI) for the other 33 EWSs were 0.611 (0.568-0.654) to 0.710 (0.675-0.745) (cardiac arrest); 0.570 (0.553-0.568) to 0.827 (0.814-0.840) (unanticipated ICU admission); 0.813 (0.802-0.824) to 0.858 (0.849-0.867) (death); and 0.736 (0.727-0.745) to 0.834 (0.826-0.842) (any outcome). NEWS has a greater ability to discriminate patients at risk of the combined outcome of cardiac arrest, unanticipated ICU admission or death within 24h of a NEWS value than 33 other EWSs.