ViEWS--Towards a national early warning score for detecting adult inpatient deterioration.
OBJECTIVE
To develop a validated, paper-based, aggregate weighted track and trigger system (AWTTS) that could serve as a template for a national early warning score (EWS) for the detection of patient deterioration.


METHODS
Using existing knowledge of the relationship between physiological data and adverse clinical outcomes, a thorough review of the literature surrounding EWS and physiology, and a previous detailed analysis of published EWSs, we developed a new paper-based EWS - VitalPAC EWS (ViEWS). We applied ViEWS to a large vital signs database (n=198,755 observation sets) collected from 35,585 consecutive, completed acute medical admissions, and also evaluated the comparative performance of 33 other AWTTSs, for a range of outcomes using the area under the receiver-operating characteristics (AUROC) curve.


RESULTS
The AUROC (95% CI) for ViEWS using in-hospital mortality with 24h of the observation set was 0.888 (0.880-0.895). The AUROCs (95% CI) for the 33 other AWTTSs tested using the same outcome ranged from 0.803 (0.792-0.815) to 0.850 (0.841-0.859). ViEWS performed better than the 33 other AWTTSs for all outcomes tested.


CONCLUSIONS
We have developed a simple AWTTS - ViEWS - designed for paper-based application and demonstrated that its performance for predicting mortality (within a range of timescales) is superior to all other published AWTTSs that we tested. We have also developed a tool to provide a relative measure of the number of "triggers" that would be generated at different values of EWS and permits the comparison of the workload generated by different AWTTSs.
Prytherch
David R
DR
Portsmouth Hospitals NHS Trust, United Kingdom.
Smith
Gary B
GB
Schmidt
Paul E
PE
Featherstone
Peter I
PI
D000368:Aged; D003422:Critical Care / Q000379:methods*; D042241:Early Diagnosis; D005260:Female; D005500:Follow-Up Studies; D006305:Health Status Indicators; D006323:Heart Arrest / Q000175:diagnosis*; D006753:Hospital Records; D006801:Humans; D007297:Inpatients / Q000706:statistics & numerical data*; D007362:Intensive Care Units; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods*; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods