Fig. 2. Performance comparison in terms of Specificity at greater than either 90% (topmost row) or 95% (other rows) Sensitivity (y-axis) for different prediction horizons ahead of observed mortality events (in hours, x-axis) for CovEWS (light green), CovEWS (linear; light purple), Liang et al. (orange)¹⁸, COVID-19 Estimated Risk for Fatality (COVER_F; blue)¹⁹, Sequential Organ Failure Assessment (SOFA; green)¹⁴, Modified Early Warning Score (MEWS; turquoise)²³, and Yan et al. (red)¹⁷ on the held-out Optum test set, the external TriNetX test set, and selected patient subgroups from the Optum test set.

Some methods do not reach 90% and 95% sensitivity for some horizons, and may therefore not be visible in all plots. Bars indicate median and error bars indicate 95% confidence intervals (CIs) obtained via bootstrapping with 200 samples. Detailed results are available in "Performance Evaluation’’. One-sided Mann-Whitney-Wilcoxon tests were used to derive p values shown at the top of each plot for superiority of CovEWS over CovEWS [linear].