Important piece. It echoes my own frustrations with many public health researchers and policy makers. It really shocked me to learn how little poorly many people working in this area understand the value of randomisation or empiricism generally.

A word in favour of observational studies. Resources devoted to these are not a major issue. Having worked on large community based RCTs in cancer screening (10s of thousands of participants) I would guess that observational studies with routinely collected data would typically be several orders of magnitude cheaper. Of course the RCTs still need to be done! But supporting observational evidence doesn't fundamentally alter the resourcing needed and can generate additional knowledge.

To put it a different way, how many large RCTs are required to arrive at the optimal masking policy? 10? 100? There are so many combinations of mask type, rules for when it can be removed, fitting etc. Head-to-head trials for comparison of all options are probably not possible. The best approach may be to establish the efficacy (or not) of masking with 1 or 2 large RCTs, and then attempt to learn at the margins with observational studies.

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Nice article.

The Bangladesh mask study was debunked by several researchers.

See here for example: https://www.researchgate.net/publication/360320982_The_Bangladesh_Mask_study_a_Bayesian_perspective

So effectively, there are no study conclusively showing that masks are effective...

Which has been clear for over a century to whoever applied the mechanical approach, as in physics classical mechanics ;)

On the other hand, we have loads of conclusive studies on the detrimental (side)-effects of masks.

The only reasonable thing to do at this point would be to forbid masks as a medical intervention against covid (and probably any airborne virus).

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Several statisticians eviscerated the Bangladesh study. WM Briggs may have been one of them, can’t remember though.

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Nice article. Couldn't agree more.

Acting (or failing to act) on the basis of high-quality, real-world, evidence has been a disaster during the pandemic, not just from a medical perspective but in every aspect of our preparation and response. And it continues to happen; the pandemic has been *over* as a serious public health threat in the UK for 18 months - yet the evidence is studiously ignored and we continue to "debate" the effectiveness of masks and how many unproven jabs should a 5 year old child be given.

But it's not just the pandemic. People behave on an anti-scientific emotional basis on *everything* these days - the intentional result of the "Long March Through the Institutions" - and it happens everyday in business decisions just as much as in politics.

The biggest danger to civilisation today is the insane climate alarmism which is driving the self-destruction of society. Based on "evidence" every bit as flaky as the masks, lockdowns and jabs, the "net zero" lunacy will lead to true catastrophe. And it's being driven by the very same Useful Idiots:


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Forgot to add one thing on the pandemic specifically, in support of your article.

The FDA website *still* contains this gem - *30 months after ther pandemic began*.

"Clinical trials assessing ivermectin tablets for the prevention or treatment of COVID-19 in people are ongoing"

Of course, this is not just ignorance or incompetence. IVM and, prophylactics / therapeutics in general have been intentionally sidelined in order to promote the "miracle" new vaccine technologies. That worked out well. Pesky evidence.

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I did physics research once upon a time. My credential is shown by my ability to find the following article via google search:

Title: "Droplet evaporation on porous fabric materials"


"Droplet evaporation on porous materials is a complex dynamic that occurs with spontaneous liquid imbibition through pores by capillary action. Here, we explore water dynamics on a porous fabric substrate with in-situ observations of X-ray and optical imaging techniques. We show how spreading and wicking lead to water imbibition through a porous substrate, enhancing the wetted surface area and consequently promoting evaporation. These sequential dynamics offer a framework to understand the alterations in the evaporation due to porosity for the particular case of fabric materials and a clue of how face masks interact with respiratory droplets."


I was researching the background of physics of masking--especially wicking and evaporation of droplets. After evaporation, some sort of residue is left, which may cling to masks--or maybe not. Physics would need to research this.

Most mask advocates consider only the ideal case and ignore what can go wrong. NIOSH is especially expert at looking at what can go wrong with masks, but has yet to make any strong statement wrt masks and respiratory droplets. NIOSH recommendations about training, use, wear, and handling wrt masks are quite complicated and not likely followed at any health care facility. No studies have been done on carrying capacity of N95s wrt respiratory droplets that I have been able to find.

CDC is out of field wrt mask advocacy, as are MDs. But ICU nurses can always express their opinions. ;)

Imo opinion as a physicist: cloth and medical masks have no impact on viral transmission. I am agnostic about the appropriateness of N95 masks for HCWs generally, awaiting more research. The general public has no business wearing masks. Research into the mechanics of masking by physics is essential and will supplement lines of evidence from other disciplines.

I hope this comment is helpful.

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