Relationship between angiopoietin-2 and IL-6 and in-hospital mortality in the derivation and validation cohorts in patients with COVID-19. Day 1 (blue columns) and day 3 (red columns) angiopoietin-2 levels according to survivors and nonsurvivors in the derivation (A) and validation (B) cohorts. Day 1 (blue columns) and day 3 (red columns) IL-6 levels according to survivors and nonsurvivors in the derivation (C) and validation (D) cohorts. In-hospital mortality according to 3-day course of angiopoietin-2 in the derivation (E) and validation (F) cohorts. In-hospital mortality according to 3-day course of IL-6 in the derivation (G) and validation (H) cohorts. Red line, increase of at least twofold from baseline; blue line, no increase.