et al., The Journal of Clinical Endocrinology & Metabolism, doi:10.1210/clinem/dgaa733 (Peer Reviewed)
Retrospective 216 COVID-19 patients and 197 population controls.
Vitamin D deficiency was found in 82.2% of COVID-19 cases and 47.2% of population-based controls (P
Authors note: "We did not find any relationship between vitamin D concentrations or vitamin deficiency and the severity of the disease". While no association was found within hospitalized patients, this statement is incorrect because there is an association with hospitalization, and hospitalization is an indication of COVID-19 severity.
Hernández et al., 10/27/2020, retrospective, Spain, Europe, peer-reviewed, 12 authors.
risk of combined death/ICU/ventilation, 83.0% lower, RR 0.17, p < 0.001, high D levels 35, low D levels 162, >= 20ng/mL risk of hospitalization * risk of death/ICU/ventilation | hospitalization.
risk of combined death/ICU/ventilation if hospitalized, 12.0% lower, RR 0.88, p = 0.86, high D levels 35, low D levels 162, >= 20ng/mL risk of death/ICU/ventilation | hospitalization.
risk of hospitalization, 80.6% lower, RR 0.19, p < 0.001, >= 20ng/mL.
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.