Letter to the editor
Just because you see something on social media or in some magazine or paper does not mean that it is true or honest or accurate. In fact, many times it is not. I am continually urging people to question what they see and hear, to do some of their own fact checking, to do some of their own thinking, to assess the validity of claims, and to accept what is confirmed to be true, and to discard the rest. And you will probably discard the majority.
A case in point. A letter to the editor in the paper last week made the following claims: “Since I wrote the April 27th letter, there was a new mask study published based on the experience of 117,000 Welsh citizens. It showed that masks didn’t work. Covid infection rates were higher among the masked. In addition, those wearing masks had more deaths and higher health care usage.” Is this true? Let’s do some fact checking.
Here is the study: Did the UK’s public health shielding policy protect the clinically extremely vulnerable during the COVID-19 pandemic in Wales? Results of EVITE Immunity, a linked data retrospective study (https://www.sciencedirect.com/science/article/pii/S0033350623000628?via%3Dihub#bib28). This study identified approximately 117,000 people considered at “highest risk of harm from COVID-19 infection,” and followed this group for a period of one year. The study took place from March 2020 to May 2021.
The study cohort included persons with the following conditions: severe respiratory condition (35.5%), people on immunosuppressive therapy (25.9%), people with cancer (18.6%), and a number of other less common conditions. In other words, some of the most medically compromised, least healthy, or sickest members of society. This is an at risk group. The control group was the rest of the general population of about 3 million people.
The intervention being assessed was a policy to promote “shielding.” One fault of this research paper is that it fails to define what measures were included in the “shielding” guidelines. Further searching yielded this report which includes a table specifying the shielding guidelines in place at the time of this Welsh study: Evaluation of the shielding initiative in Wales (EVITE Immunity): protocol for a quasiexperimental study (https://bmjopen.bmj.com/content/12/9/e059813#T2). Here are the key points included in the shielding guidelines: “Do not leave the house to go to work or to see other people. Avoid being in the same room as another person. Keep three steps away from another person in the home. Avoid sharing kitchen, bathroom or bedroom facilities with others in the home. Eat meals separately from other household members.” The study group was given specific instructions to “shield,” while the control group was not (even though during this time frame most people in many countries were asked to do some level of shielding, and it is likely many in the control group were also shielding to some extent). Here in BC we used the terms self-isolation and social distancing.
And the conclusions?
Regarding Covid infection rates: The authors state that the known Covid infection rate among the shielded group was 5.9% compared to 5.7% among the non-shielded group, but provide no indication of where those numbers came from. A few paragraphs later they state “we have no data on which to estimate where the true rate of [Covid] infection should lie – we therefore present a range of 5.9-15.9% in the shielded cohort and 5.7-18.7% in the non-shielded cohort.” In other words, the Covid infections rates were essentially the same. And depending on your bias, you could report the low end numbers and conclude the shielded group is at greater risk of Covid infection, or you could report the high end numbers and conclude the non-shielded group is at greater risk of Covid infection.
Regarding death rates and health care usage: The authors report higher death rates and greater utilization of healthcare among the shielded group. But keep in mind this group is composed of those at “highest risk of harm from COVID-19 infection.” This cohort is medically compromised – some of the least healthy or sickest members of society. This group will always have a higher utilization of health care services and a higher death rate, with or without Covid, with or without shielding. As the authors state: “Higher rates of mortality and health service utilisation were to be expected in a clinically vulnerable population.”
Regarding the efficacy of a policy that promotes shielding: The authors conclude that the policy to promote shielding among those at “highest risk of harm from COVID-19 infection” did not significantly reduce Covid infection rates among this group.
Regarding masks: There is no mention of masks anywhere in this study, nor in any of the references that I could find on shielding guidelines in place at the time of this study. Therefore, it is not possible to draw any conclusions regarding masks.
Now go back and reread the claims published in last week’s letter to the editor. Look up that research paper “based on the experience of 117,000 Welsh citizens.” Compare the conclusions I have written. And you decide who has presented a true or honest or accurate summary of that research paper. Specifically, consider whether the claims regarding mask wearing in last week’s paper are supported by the Welsh study that was cited as evidence.
If you were to substitute the word “shielding” in place of “masks” in last week’s letter, you would have a reasonably accurate summary of the Welsh study. “Since I wrote the April 27th letter, there was a new shielding study published based on the experience of 117,000 Welsh citizens. It showed that shielding didn’t work. Covid infection rates were higher among the shielded [biased claim – as I note above]. In addition, those shielding had more deaths and higher health care usage.” It seems the error was in assuming “shielding” meant “masking,” when in fact it was totally different. And it is unfortunate that one journalistic summary of this research paper (which also makes no mention of masks) is accompanied by a photo of a person wearing a mask (https://www.swansea.ac.uk/press-office/news-events/news/2023/04/new-study-no-evidence-that-shielding-reduced-covid-19-infections-in-wales.php).
We all desire to live the best lives we can. And in that pursuit we all make decisions regarding what we will or will not do, and how we will do it. These decisions have consequences that will either benefit us or place us at risk. It is therefore important to base our decisions on reliable and truthful information.
Regarding the subject of this letter, think carefully and honestly about the truthfulness of those claims regarding adverse effects from mask wearing.
Jeff Corbett
McBride, BC
