“Absolute risk, simply explained, is “the likelihood that an outcome will occur.”
Relative risk “compares the risk of a health event … among one group with the risk among another group.”
Pfizer told the FDA that eight (of approximately 22,000) volunteers in its vaccine group developed a PCR-confirmed case of COVID-19, versus 162 of 22,000 volunteers in the placebo group. Moderna reported a similar spread — five out of 15,000 in the vaccine group versus 90 out of 15,000 in the placebo group.
When one does the math, the Pfizer clinical trial numbers showed: “The risk reduction in absolute terms [was] only 0.7%, from an already very low risk of 0.74% [in the placebo group] to a minimal risk of 0.04% [in the vaccine group].” (Dividing 0.7 — the difference between the two groups — by 0.74 is the mathematical calculation that produced the touted “95% effective” number).“
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