Dr. Scott Atlas, former chief of neuroradiology at Stanford University Medical Center and a senior fellow at Stanford’s Hoover Institution, called a recent study purporting to measure the effect of masking on curbing the spread of Covid-19 in Bangladeshi villages “extremely weak tea” during a Fox News appearance earlier this month.
The randomized trial, the results of which were posted September 1 by the nonprofit organization Innovations for Poverty Action and are currently being peer reviewed, measured over 340,000 people in 600 villages. It claims to show that an increase in the usage of surgical masks can lead to a reduction in the spread of the virus in certain age groups (via NBC News).
For five months beginning last November, [study co-author Mushfiq] Mobarak and his colleagues tracked 342,126 adult Bangladeshis and randomly selected villages to roll out programs to promote their usage, which included distributing free masks to households, providing information about their importance and reinforcing their use in the community.
Among the roughly 178,000 individuals who were encouraged to wear them, the scientists found that mask-wearing increased by almost 30 percent and that the change in behavior persisted for 10 weeks or more. After the program was instituted, the researchers reported an 11.9 percent decrease in symptomatic Covid symptoms and a 9.3 percent reduction in symptomatic seroprevalence, which indicates that the virus was detected in blood tests.
While the effect may seem small, the results offer a glimpse of just how much masks matter, Mobarak said.
“A 30-percent increase in mask-wearing led to a 10 percent drop in Covid, so imagine if there was a 100-percent increase — if everybody wore a mask and we saw a 100-percent change,” he said.
The scientists said masks significantly reduced symptomatic infections among older adults, and found that surgical masks were more effective than cloth versions.
Appearing earlier this month on Fox News’ “The Ingraham Angle,” Atlas called the fact that the study was randomized “important” before citing a similarly randomized study from Denmark conducted last year that showed that “individuals wearing masks do not have a lower risk of infection testing for virus than people wearing masks.”
“This is a different type of study,” said Atlas, a frequent and early lockdown critic who briefly served as a member of former President Donald Trump’s White House coronavirus task force last year. “This tests to see if people in a village get symptomatic Covid if the villagers wear masks versus other villages that don’t wear masks as much.”
The Hoover Institution fellow went on to describe two results from the study before explaining why he feels it’s hardly the definitive evidence pro-maskers have been searching for these past 18 months.
Er, about that Bangladesh mask study, Dr. Scott Atlas has some thoughts.
“This is what I would call extremely weak tea … It’s been oversold. People are so desperate to find some pebble somewhere that shows that masks work.” pic.twitter.com/tKlAgRWJCb
— Scott Morefield (@SKMorefield) September 2, 2021
One, in people defining Covid as symptoms plus anti-bodies, there is no evidence that cloth masks have any impact, no significant impact with cloth masks for people who have Covid as defined by Covid symptoms with antibody documentation. So cloth masks are worthless according to this study.
The second part is the surgical mask study. And the surgical mask study shows that there is from my reading here about an 11% decrease in individuals having symptomatic Covid with antibodies. 11%. And basically only older people. So what this shows you after all is said and done is it confirms that cloth masks are worthless. It shows – if you take the data at face value – a very minimal impact, 11%, decrease in symptomatic cases in mask usage by the village.
And so, you know, of all the clamoring for something desperately to show that masks work, this is what I would call extremely weak tea. In fact, it confirms the reason why we have seen all over the world and in the United States that mask usage by the population does not significantly stop the spread of the virus.
It’s being oversold, but people are desperate to find some pebble somewhere that shows masks work.
Atlas, by far, wasn’t the only critic. Professor Francois Balloux, director of the UCL Genetics Institute and professor of computational biology at University College London, tweeted that it’s “not obvious” from the study that masks are “statistically significantly associated with reduced transmission at the level of the population.”
I don’t wish to enter the mask debate. I’ll just make one point. When the data from this trial is analysed conventionally, it’s not obvious that masks (including surgical ones) are statistically significantly associated with reduced transmission at the level of the population.
— Prof Francois Balloux (@BallouxFrancois) September 1, 2021
As much as the earlier Danish study could not be interpreted as “masks don’t work”, this one doesn’t demonstrate “masks do work”. Science can be a pain in the neck. It’s a slow and iterative process. I’m sorry.
— Prof Francois Balloux (@BallouxFrancois) September 1, 2021
Nick Hudson, chairman of Pandata.org (PANDA), tweeted a blog post by Substack writer el gato malo titled, “bangladesh mask study: do not believe the hype,” calling it “sound commentary.”
Sound commentary on the Bangladesh mask study: “This is one of the worst studies i’ve ever seen in any field. It proves nothing apart from the credulity of many mask advocates.”https://t.co/8IGQbov3nz
— Nick Hudson (@NickHudsonCT) September 5, 2021
From el gato malo’s analysis:
To claim that masks caused any given variance in outcome, you need to isolate masks as a variable. They didn’t. This was a whole panoply of interventions, signage, hectoring, nudges, payments, and psychological games. It had hundreds of known effects and who knows how many unknown ones.
We have zero idea what’s being measured and even some of those variables that were measured showed high correlation and thus pose confounds. when you’re upending village life, claiming one aspect made the difference becomes statistically impossible. the system becomes hopelessly multivariate and cross-confounded.
The authors admit it themselves (and oddly do not seem to grasp that this invalidates their own mask claims)
Gato’s post has gotten lots of attention on Twitter for its thoroughness.
So here’s one critical response to the Bangladesh mask study. It is a harsh response but seems carefully thought through to me. I confess that I am out of my depth with the science of randomised trials, so I welcome expert input!
— David Thunder (@davidjthunder) September 2, 2021
Cat Litter: Bangladesh mask study methodically eviscerated for its intractable flaws. “this is one of the worst studies i’ve ever seen in any field. it proves nothing apart from the credulity of many mask advocates” https://t.co/LjsojEOLY5
— Andrew Bostom, MD, MS (@andrewbostom) September 2, 2021
Harvard professor Dr. Martin Kulldorff called it “odd” that “mask advocates are excited by this study.”
Odd that mask advocates are excited by this study. As a vaccine advocate, I would be horrified if a vaccine trial showed 11% efficacy. Based on the 95% confidence intervals, we do not even know if surgical mask efficacy is more than 0%. https://t.co/N7d5bjbxxe
— Martin Kulldorff (@MartinKulldorff) September 1, 2021
David Chavous, an attorney with a PhD in molecular biology, called the fact that results were only seen for those over 50 years old a “HUGE red warning sign.”
Okay, one last thing about the Bangladesh mask study: the results showing over >50 only should be a HUGE red warning sign. Why would it matter? They needed to chase this down. This could be sociological and not mechanistic. We just don’t know.
— David Chavous (@DACDAC4DAC) September 1, 2021
Others called attention to the negligible effects of cloth mask use in the study – the type of mask most people use.
Mask proponents in the USA are wildly celebrating a study from Bangladesh which they think validates mask usage here, but actually quashes cloth masks–the cornerstone of American mask policy.
If this isn’t peak COVID horse-blinder Scientism, I don’t know what is.
— BOUTROS ? (@boutros555) September 1, 2021
Big news on Twitter today. Bangladesh study w/342,146 adults finds “Masks Work!”
Well, “Surgical Masks Work!”
I mean, “Surgical Masks Work if You’re Over 50!”
— Karl Dierenbach (@Dierenbach) September 1, 2021
Sorry for my lack of clarity — The Danish study studied surgical masks mainly. The Bangladeshi study looked at cloth and surgical masks. The efficacy estimates from the two studies on surgical mask efficacy are strikingly close and very low.
— Jay Bhattacharya (@DrJBhattacharya) September 2, 2021