Retrospective 19 European countries showing countries with mean vitamin D levels > 50nmol/L have a 2.2 times lower risk of mortality (p
= 0.032) compared to those with mean levels < 50 nmol/L.
Ahmad et al., 3/12/2021, preprint, 4 authors.
risk of death, 53.6% lower, RR 0.46, p = 0.03, >50nmol/L.
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.