Figure 3. Serum 25-Hydroxyvitamin D Levels in a Study of the Effect of a High Dose of Vitamin D₃ on Patients With Moderate to Severe Coronavirus Disease 2019.

Serum 25-hydroxyvitamin D levels were measured on the day of randomization (baseline) and on hospital discharge (postintervention). A, For all patients, a single high dose of vitamin D₃ significantly increased 25-hydroxyvitamin D levels compared with placebo (difference, 24.1 ng/mL [95% CI, 19.5-28.7]; P < .001). Median (interquartile range) observation time of the postintervention period was 7.0 (4.0-10.0) days for the vitamin D₃ group and 7.0 (5.0-13.0) days for the placebo group. B, For patients with 25-hydroxyvitamin D deficiency, a single high dose of vitamin D₃ significantly increased 25-hydroxyvitamin D levels compared with placebo (difference, 22.7 ng/mL [95% CI, 19.3-26.1]; P < .001). Median (interquartile range) observation time of the postintervention period was 8.0 (4.0-11.5) days for the vitamin D₃ group and 7.0 (6.0-13.3) days for the placebo group. Boxes represent median and interquartile range and whiskers extend to the highest and lowest values within 1.5 times the interquartile range of the 25th and 75th percentiles. Circles represent outliers.