Figure 2. Kaplan-Meier Plot of the Probability of Survival Until Day 28 After Enrollment.

Vital status was known through study day 28 for 194 patients (94.2%). The median duration of follow-up was 28 days (interquartile range, 28-28 days) in both study groups. Vertical ticks on the curves indicate censoring due to loss to follow-up after hospital discharge.