Dawlish: Devon is 'pretty close' to PM's booster jab target, health boss says

Are Pfizer and Moderna misleading the public about the efficacy of their COVID vaccines by withholding the fact that there’s another way to parse their data — one that has more real-world significance?

In his introduction, Huff wrote: “Averages and relationships and trends and graphs are not always what they seem.” He added: “There may be more in them than meets the eye, and there may be a good deal less.”

Almost 70 years later, Huff’s admonition that a “well-wrapped statistic” can “sensationalize, inflate, confuse and oversimplify” seems more relevant than ever. For a pertinent modern-day example, one need look no further than COVID vaccine developers’ “headline-worthy” but misleading claims about their products’ “95% effectiveness.” As BMJ associate editor Peter Doshi and others have been confirming for months, these efficacy data are largely a matter of statistical smoke and mirrors.

Why are manufacturers’ claims about vaccine effectiveness misleading? Pfizer and Moderna declined to share with the public the fact that there is another way to parse their data that has more real-world significance.

Examining a statistic called absolute risk reduction — the number of percentage points that an individual’s risk goes down if they do something “protective” — the two companies’ COVID vaccines barely make a dent at all, reducing someone’s risk of experiencing COVID symptoms (the clinical trials’ endpoint) by less than 1%. This is the practical number that people are likely to care about most.

Knowing the paltry real-world impact of the injections on someone’s risk of developing COVID symptoms, how many people swayed by the misleading “95% effective” mantra might instead have decided to refuse the vaccines — products that have revealed themselves to be highly unsafe and, in some cases, fatal?

Unfortunately, topping its November efficacy claims for people 16 years and older, Pfizer just announced its COVID injection is “100% effective for 12-to-15 year-olds.” This announcement sets the stage for the U.S. Food and Drug Administration’s (FDA’s) predicted authorization of Pfizer’s unlicensed vaccine for the adolescent market.

Parents who know that COVID rarely poses a threat to children and adolescents may already be planning to keep their kids away from the experimental shots, but there are other reasons for taking Pfizer’s latest grandiose claims with a grain of salt.

Absolute vs. relative risk

In November — just before the FDA issued its initial Emergency Use Authorization (EUA) for Pfizer’s COVID vaccine — Doshi cautioned the public that Pfizer’s and Moderna’s efficacy results seemed dramatic only because the companies derived them from relative risk data.

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).

Dawlish Discussion

Dawlish: Devon is 'pretty close' to PM's booster jab target, health boss says