Fig. 4

P/F and SOFA scores following high-dose intravenous vitamin C treatment. a The bars show the standard deviation (SD) of the mean. The P/F in both groups was approximately 200 at enrollment. After initiation of treatment, there was a steady rise in the P/F in the HDIVC group and a decline in the P/F in the placebo group (day 3: 217 vs. 189, 95% CI -34 to 90, P = 0.37; day 7: 229 vs. 151, 95% CI 33 to 122, P = 0.01). b △7 of P/F means the difference between the value from Day1 to Day7. Boxes represent the median and interquartile range (25th and 75th percentiles), and whiskers represent the range of values. The delta P/F ratio showed a different result in two groups (20.0 ± 96.68 vs. -51.88 ± 150.72, P = 0.04, 41.02 (5.92–172.45)). △7 was calculated by the difference between the value from Day 1 to Day 7. c The bars showed the interquartile range (IQR) of the median. There was no difference in the initial Sequential Organ Failure Assessment (SOFA) scores of the 2 groups at baseline (vitamin C vs placebo, median, 3.5[3.0–6.8] vs 2.0 [3.0–5.0]). After 7-day treatment, the median of SOFA score increased from 2.0 to 6.0 in the placebo group and slightly decreased from 3.5 to 3.0 in the HDIVC group, but there was no difference between the 2 groups. d △7 of SOFA scores means the difference between the value from Day1 to Day7. Boxes represent the median and interquartile range (25th and 75th percentiles), and whiskers represent the range of values. The delta SOFA scores showed no significant difference in two groups (0.0[-2.75-1.0] vs. 0.0[-1.0-3.5], P = 0.25, CI -1.35(-3.04-0.34)). △7 was calculated by the difference between the value from Day 1 to Day 7. HDIVC high-dose intravenous vitamin C, SOFA Sequential Organ Failure Assessment, P/F PaO₂/FiO₂COVID-19 coronavirus disease 2019