Analysis of vitamin D and zinc levels in 53 PCR+ outpatients and 53 controls, showing lower zinc levels in COVID-19 patients, and increased risk of symptomatic cases with vitamin D deficiency. Currently only the abstract is available.
Golabi et al., 8/26/2021, retrospective, Iran, Middle East, preprint, 10 authors.
risk of symptomatic case, 81.0% lower, RR 0.19, p < 0.001, >30ng/mL vs. <20ng/mL, RR approximated with OR.
This study is excluded in the after exclusion results of meta analysis: detail too minimal.
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.