Peter McKnight: How Anti-Vaccines Misinterpret Data to Make Their ‘Case’

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Well, that didn’t take long. When news of the death of former US Secretary of State Colin Powell was just beginning to resonate around the world, anti-vaccines were already on the case, insisting that his passing was proof positive that vaccines they do not work.

Never mind that Powell, fully vaccinated, was 84 years old, had multiple myeloma and Parkinson’s disease, and was probably severely immunosuppressed. Apparently, a single death of a vaccinated individual is ipso facto proof of the futility of vaccines. And a lot of death or serious illness, well that’s a hit.

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Late this summer, vaccine skeptics highlighted some curious facts from Israel, revealing that more vaccinated than unvaccinated people were hospitalized with COVID-19. Judging from conversations on the internet, not to mention my inbox, this dataset continues to fuel worldwide skepticism about COVID vaccines, skepticism that will now likely intensify with Powell’s death.

Now it is true that on August 15, 2021, vaccinated Israelis accounted for nearly 60 percent of hospitalized COVID patients, as 301 vaccinated patients were hospitalized compared to 214 unvaccinated people.

Needless to say, vaccine skeptics have suggested that this demonstrates the danger of vaccines. But in fact, it is the data itself that is dangerous; specifically, the fact that “aggregated” data often paint a very different picture from that sketched by the data components, a phenomenon known in statistics as Simpson’s paradox.

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In a masterful missive, Biostatistician Jeffrey Morris explains how the Israeli data gave rise to this phenomenon. Morris notes that the aggregated data does not take into account “confusing” variables such as relative age and vaccination status, which produces a very misleading picture.

For example, when the Israeli data was published, more than 80% of Israelis had been vaccinated. So while more vaccinated people were hospitalized, they accounted for a much smaller percentage than the percentage of unvaccinated Israelis sick with COVID. In fact, 5.3 vaccinated people per 100,000 were hospitalized compared to 16.4 unvaccinated people per 100,000.

When we consider age as well as vaccination status, things are even more dramatic. As is the case in many countries around the world, older people in Israel are more likely to be vaccinated and more likely to suffer from serious respiratory illnesses. And, in fact, people over the age of 50 accounted for the majority of COVID hospitalizations.

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Of the 301 people vaccinated at the hospital, a total of 290 were over 50 years old. And of the 214 unvaccinated patients, 171 were over 50 years old. This, then, is another example of how the vaccinated outnumber the unvaccinated.

However, since more than 90 percent of older Israelis were vaccinated, the 170 unvaccinated patients were drawn from an extremely small group of people. So, while the hospitalization rate for vaccinated seniors was 13.6 per 100,000, unvaccinated seniors were hospitalized at a rate of 90.9 per 100,000, almost seven times higher than their vaccinated counterparts.

Interestingly, while Israeli data was receiving worldwide attention, a very similar phenomenon was quietly occurring in British Columbia. Between August 7 and September 3, the BC Center for Disease Control reported 48 percent of COVID deaths occurred among vaccinated people, compared with 46 percent among unvaccinated. Partially vaccinated people made up the remaining six percent.

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Without further examination, this would suggest that vaccines are, at best, useless in preventing death. But in presenting these statistics, the BCCDC wisely emphasized that the high percentage of deaths from vaccination was a product of the fact that the majority of deaths occurred among older people, and more than 90 percent of those people were vaccinated.

And as more young people have been vaccinated since this data was published in British Columbia and Israel, the number of hospitalizations and deaths among vaccinated people has fallen below those of the unvaccinated. According to the BCCDC, between September 4 and October 1, 36% of COVID deaths occurred among vaccinated people, compared to 57 percent among unvaccinated.

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None of this is likely to influence hardcore anti-vaccines, of course. But for the rest of the vaccine skeptics, and for all of us, it is a lesson that data, like any valuable object, must be handled with care.

Peter McKnight’s column will appear weekly in the Sun. He can be reached at [email protected]

Letters to the editor should be sent to [email protected]. The editor of the editorial pages is Hardip Johal, who can be contacted at [email protected].

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