Thats not what the study actually says.
Now, lets see what the study was actually about.
What question was the study designed to answer?
The study setting wasnt very much like the world were living in now.
Cases were low, and most people were not wearing masks.
The study was not blinded, because obviously you know whether you are wearing a mask.
Participants tested themselves for antibodies and reported on a survey whether they had worn the masks according to instructions.
What did they find?
The investigators did not see the drastic reduction in infection they were hoping for.
Did they see asmallreduction in risk?
If masks reduced risk by a lower amount25%?
10%?the study wasnt able to detect that.
Thats a large range of possibilities because the study wasnt designed to tell the difference between any of them.
Bottom line - you wearing a mask probably wont halve your risk of infection.
(Mask wearing was uncommon in Denmark at the time.)
(Denmark was in lockdown during most of the study.)
The study did not test a country-wide mask mandate (again, there was none).
The study did not test whether masks prevent you from spreading the coronavirus if you are sick.
(It only looked at the infection risk for the wearer.)
The study did not test masks directly, only what happens when you advise people to wear them.
This study did not separate the two.)
As the CDC recently clarified, we haveother evidence that masks probably benefit the wearer.
We kind of already knew that, didnt we?
Keep wearing your mask.
