Even True Numbers can be Deceiving

 

I have noticed that some people who welcomed vaccines have from time to time become dispirited by the numbers. Some of them think the recent numbers have shown that vaccines are not effective, and perhaps they have wasted efforts to get them.  That is an unfortunate thing, because the vaccines have been very effective.  I am grateful to the reporters and columnist at the Winnipeg Free to make this clear.  They have been providing an invaluable public service. They strongly suggest that in Manitoba at least the province could do a much better job in presenting the numbers on Covid-19 that make this clear. Instead, the government has been presenting numbers in a way that can facilitate the arguments of the Resisters.

The province of Manitoba presents summaries of the data it has collected on Covid-19 in what it calls a “dashboard.” This is exactly where it could do a better job according to experts.  In fact, some non-experts (like me) have been griping about this.

Superficially the province presents its information in a comprehensible manner because it includes the number of recent Covid-19 cases and the number of those that were vaccinated and those that were unvaccinated. Unfortunately, that is not enough to allow one to compare apples to apples and oranges to oranges. To do that we need more information. Specifically, the numbers must take into consideration two very important facts.

First, the numbers must be presented in such a way that the numbers show the proportion of the population that is vaccinated compared to the population that is not vaccinated. Without information like that the numbers presented by the province are seriously misleading and that is exactly what the province should not do in a pandemic.

I’ll give an example.  A recent dashboard showed that nearly half of recent Covid-19 cases in Manitoba were among fully vaccinated people. Sounds bad for vaccinated people doesn’t it? Why bother?  But presenting numbers that way without the context of the number of vaccinated people relative to the number of unvaccinated people is seriously misleading. People can easily be deceived. The way the province presents the numbers in its Dashboard does not show the true risks to Manitobans who have not yet been vaccinated. The way the numbers are presented can lull them into a false sense of security.

Prof. Nazeem Muhajarine of the University of Saskatchewan community health has pointed out that “the Manitoba dashboard lacks basic population information that would provide crucial context for the number of infections being reported among vaccinated and unvaccinated people.”

That is exactly the point, without the crucial context, people will tend to underestimate the benefits of vaccines.  And that result is disastrous in a pandemic where we urgently need more people to understand the risks and the choices they make. This is what Danielle Da Silva said in the Winnipeg Free Press,

“A government dashboard showing nearly half of recent COVID-19 cases in Manitoba were among fully vaccinated people is misleading and fails to clearly represent the risk the disease poses to people who have yet to take the jab, experts say.”

 

The Manitoba Dashboard does what you would think, it discloses the number of new COVID-19 cases, hospitalizations and intensive care admissions by vaccination status on its pandemic dashboard each weekday, but as Da Silva explained that is not enough.

Here is an example that Da Silva presented:

“According to the dashboard, 48 per cent of COVID-19 cases reported in the past two weeks were in fully vaccinated people and 44 per cent were in unvaccinated people. Meanwhile, on Tuesday, the province reported 88 new cases in fully vaccinated people and 61 cases in unvaccinated people.”

 

That is all true but it’s misleading. It doesn’t give us enough information to really understand what is going on.

The snapshot of daily data has since been shared on various social media channels and in anti-vaccination circles to cast doubt on the efficacy of COVID-19 vaccines.

Da Silva interviewed a Professor from the University of Saskatchewan community, Nazeem Muhajarine, who said what was missing was basic population information that makes such information useful.  Manitoba should provide population information that gives context. As the Professor said, ,

 “Reporting this type of incomplete information in the midst of a pandemic and in the midst of one of the most highly mutated variants, omicron, knocking about… is actually very alarming,” Muhajarine said in an interview with the Free Press.

The epidemiologist described the province’s dashboard as misleading, adding it can serve as evidence and ammunition for people who already believe vaccines are not going to protect against COVID-19.

“It really does send the wrong message and signal to people who might be looking for something like this,” Muhajarine said. “They will latch on to it, harp on it and basically hold this up as confirmation of what they had always been saying, of course, erroneously.”

When adjusted to account for population size, the risk of infection for unvaccinated people in the province is more than five times greater than vaccinated people, according to Doctors Manitoba.

People who have yet to be vaccinated are also 8.4 times more likely to be hospitalized with COVID-19 and 19 times more likely to end up in intensive care, the physicians association said.”

  

When you realize that in Manitoba nearly 75% of all Manitobans have been fully vaccinated while less than 29% are unvaccinated, which includes those who are not even eligible, the numbers alone don’t tell the whole story.

Keir Johnson of Doctors Manitoba told this to the Free Press, “When it comes to sharing new COVID-19 cases or severe outcomes by vaccination status, it is important to present this information in a way that allows an apples-to-apples comparison.”

Doctors Manitoba has also said the province should do a better job communicating. This is particularly important in a time of a COVID pandemic where there is also a pandemic of misinformation.  The reason the information is not good enough, Johnson explained, is

Because the number of people who are fully vaccinated is so much larger than the number of people who are unvaccinated, it makes comparing numbers misleading unless they are presented with additional information, such as a rate or relative risk.

 

In my next post I will explain how there is another piece of information missing that would make the risks even clearer.

 

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