Prospective study of 120 severe cases of COVID-19 in Algeria finding low vitamin D and low calcium both associated with increased mortality.
Bennouar et al., 1/12/2021, prospective, Algeria, Africa, peer-reviewed, 4 authors.
risk of death, 85.5% lower, RR 0.14, p = 0.002, high D levels 4 of 30 (13.3%), low D levels 15 of 32 (46.9%), adjusted per study, >30μg/l vs. <10μg/l, proportional Cox regression.
risk of death, 63.0% lower, RR 0.37, p = 0.10, high D levels 4 of 30 (13.3%), low D levels 14 of 35 (40.0%), adjusted per study, >30μg/l vs. 10-19μg/l, proportional Cox regression.
risk of death, 23.1% lower, RR 0.77, p = 0.73, high D levels 4 of 30 (13.3%), low D levels 4 of 23 (17.4%), adjusted per study, >30μg/l vs. 20-29μg/l, proportional Cox regression.
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.