This isn't a study, it's a scientific opinion piece that references studies. The seven studies that he references show a variety of things about influenza and the common cold, but primarily focus on a comparison between N95 and surgical masks.
The issue I can see with the first is that it's only 32 people which is incredibly small sample size. I would read more but there's a pay wall. It effectively concludes that larger studies need to be done.
The second concludes exactly what I said in the first place and counters the point the guy in your article was trying to make, "There is some evidence to support the wearing of masks or respirators during illness to protect others, and public health emphasis on mask wearing during illness may help to reduce influenza virus transmission. There are fewer data to support the use of masks or respirators to prevent becoming infected."
The third, basically the same conclusion, it's too long to copy/paste, but you can read it here:
https://onlinelibrary.wiley.com/doi/epdf/10.1111/j.1750-2659.2011.00307.x
The Fourth, same thing although this time they're saying that contrary to the expected result, surgical masks were within the margin of error as good at stopping airborne virus particles as n95 respirators. This suggests that unlike what the author who cited it says and what you're implying bringing up aerosols, the particle size of the virus itself is in fact a small part of it. Exactly as I said, they attach to larger particles which do get stopped by less stringent masks.
The Fifth,
https://academic.oup.com/cid/article/65/11/1934/4068747 read the part about H1N1, which is the most similar transmission. This study is much harder for me to understand so take it with a grain of salt, but it appears as part of their meta-analysis they're finding that most of the time there's a significant advantage to face coverings as well, but the difference between surgical masks and n95s are unclear, which doesn't dispute anything I've said and seems to go against the guy who cited it as well.
The Sixth, once again differentiating N95 and surgical masks: "In this pragmatic, cluster randomized clinical trial involving 2862 health care personnel, there was no significant difference in the incidence of laboratory-confirmed influenza among health care personnel with the use of N95 respirators (8.2%) vs medical masks (7.2%). As worn by health care personnel in this trial, use of N95 respirators, compared with medical masks, in the outpatient setting resulted in no significant difference in the rates of laboratory-confirmed influenza."
The seventh, once again only comparing n95 to surgical masks, "Conclusion: The use of N95 respirators compared with surgical masks is not associated with a lower risk of laboratory-confirmed influenza. It suggests that N95 respirators should not be recommended for general public and nonhigh-risk medical staff those are not in close contact with influenza patients or suspected patients."
So, in conclusion, this guy's saying, "Masks and respirators do not work. There have been extensive randomized controlled trial (RCT) studies, and meta-analysis reviews of RCT studies, which all show that masks and respirators do not work to prevent respiratory influenza-like illnesses, or respiratory illnesses believed to be transmitted by droplets and aerosol particles." and then going on to site 7 studies, 6 of which dispute his claims by accepting the benefit of masks and instead trying to differentiate between the more expensive N95 respirators and cheap surgical masks, basically he's deceptively hoping you don't click on the studies. I did, and he's full of shit. The one study that seemed to lean in his direction was the earliest one and it only involved 32 patients and 9 incidents of a virus at all. Wow. According to the author's wiki, he's also pretty famous for publishing misleading articles on global warming. What a guy.
This article references supposed studies, scientist statements, politician statements, and agency declarations, but literally doesn't contain a single actual link except to their own mega-thread offering nothing, and leans heavily on what random people say as well. I'm not going to do their work for them to find wtf they're talking about with, "Hoebe, head of infectious disease control in Zuid-Limburg, the region hit hardest when the pandemic struck Holland, pointed to a Norwegian study showing 200,000 people must wear surgical masks for one week to stop a single Covid-19 case."
The whole article can be summed up with this rather stupid snippet, "'I like it when people can decide for themselves,' said Jesus Garcia, wielding the clippers in Barbershop Jordaan filled with mask-free staff and customers. 'You would have to really educate people how to use them properly for safety.'
He said he had worn masks during a trip to Spain. 'I did not feel it was really helping since people were wearing them all wrong, putting them in their pockets, placing them under their noses. It defeats the purpose.' One customer having a trim agreed. 'I find face masks absolutely awful. They're claustrophobic and don't work,' said Mark Casey, corporate finance partner at a major accountancy firm."
This is from May and if you had read the article you would see it's entirely about the supply and infrastructure required to bring the supply up to a level where the people who are going to get the most exposure (ER nurses, etc) have enough of a supply that the needs that are secondary can be met without causing another supply catastrophe like we had early on. This is a long way away from saying they're not effective, but understand WHO and the CDC are primarily concerned about masses of populations. WHO in particular is dealing with huge supply/demand differences in different countries that can affect their guidance. A hospital with less masks because of increased demand and not enough supply is far worse for our death and infection numbers than spreading out the supply to everybody to be fair, but I think it was fairly obvious that the CDC was wrong while they were saying not to buy a mask. That guidance was more a means to a better end and I'll admit a little manipulative, but I understood why they'd minimize the effectiveness of masks during that time.
As I've mentioned before, this is a well understood conclusion. What you've effectively pointed to is a guy who cited a bunch of contrary evidence to his own point and ended up proving a different point which is that there's not much difference between n95 respirators and masks for covid-19 prevention. I can certainly agree with that, but it's a point I've already made due to particle size.
I still encourage you to read that study I linked, because it's honest about the shortcomings while showing where the science currently is. This is the part that sums it up the best, "Overall, an evidence review finds "moderate certainty evidence shows that the use of hand-washing plus masks probably reduces the spread of respiratoryviruses." Yet there's no reason to believe that it doesn't help. The first author's little thought experiment with particle sizes is equivalent to basically all of the evidence you'll find against masks.
Not really, but that's the one I know the most about. I half-expected you to say that your blood-oxygen level goes down while wearing a mask and that's largely why I wanted to explore it. I'm glad to see you haven't gone down the rabbit hole of conspiracies. Honestly I can't blame you at all for taking the 1st article at face value. If you read that it sounds convincing until you see the 6 major holes.
