evidence: No Changes in All-Cause Mortality in Pfizer’s Clinical Trial for mRNA Vaccine: Why? In the 6-month trial, 21 deaths occurred in the mRNA vaccine group and 17 in the placebo group. [...] To state this article’s conclusion early, yes, no reduction in all-cause mortality rate was seen in the mRNA vaccine group in Pfizer’s 6-month clinical trial. But there are reasons for this; for example, very few participants are at high risk of fatal Covid-19, making this trial unsuitable for studying mortality rate. Other observational studies on Covid-19 vaccines and all-cause mortality show otherwise.