Very small 42 PCR+ outpatient RCT in Mexico, 22 treated with vitamin D. Most patients had insufficient vitamin D levels, there were more symptoms in those with insufficient levels, and there were less cases with fever or with >3 symptoms at day 14 for treatment with vitamin D.
Sánchez-Zuno et al., 5/28/2021, Randomized Controlled Trial, Mexico, North America, peer-reviewed, 12 authors, dosage 10,000IU days 1-14.
risk of COVID-19 severe case, 89.4% lower, RR 0.11, p = 0.04, treatment 0 of 22 (0.0%), control 4 of 20 (20.0%), continuity correction due to zero event (with reciprocal of the contrasting arm), risk of >3 symptoms at day 14.
risk of no recovery, 80.8% lower, RR 0.19, p = 0.22, treatment 0 of 22 (0.0%), control 2 of 20 (10.0%), continuity correction due to zero event (with reciprocal of the contrasting arm), risk of fever at day 14, Table S1.
Effect extraction follows
pre-specified rules
prioritizing more serious outcomes. For an individual study the most serious
outcome may have a smaller number of events and lower statistical signficance,
however this provides the strongest evidence for the most serious outcomes
when combining the results of many trials.