Don't Be Fooled By CDC's New Mask Study
Masking is still mostly ineffective
Don't be fooled by the new CDC masking study, it wouldn’t pass for an 8th grade science experiment. The truth is, masking remains highly ineffective against SARS-CoV-2, especially in light of Omicron being so transmissible. There were many confounders (problems) in this study that make the data questionable at best. So below I will break the important details down for you in easy to understand terms. Share this with someone so they are not tricked by the CDC’s foolish work👇!
Overview
Primary analysis (what was done/tested): different kinds of masks (cloth, surgical, N95/KN95, no mask) were used to compare the odds associated with a positive test result after 14 days of either wearing it in public all, some, or none of the time, and having no exposure to others with a SARS-CoV-2 infection during that period.
This was a case control negative study so within 48 hours of testing positive the individual was contacted by phone (13% +\- picked up) and if they picked up were matched with a similar age/sex negative testing individual (8.9% +\- picked up)
The study included 652 people who tested positive after 14 days of mask wearing
The study included 1,176 people who tested negative (control)
Participants from 9 regions in California
Secondary analysis: analyzed the different types of masks worn by study participants (of which, 534 reported mask type)
Results
Cloth masks were associated with (aOR=0.44) 56% lower odds of testing positive after wearing for 2 weeks
Surgical masks were associated with (aOR=0.34) 66% lowered odds of testing positive after wearing for 2 weeks
N95/KN95s were associated with (aOR=0.17) 83% lowered odds of testing positive after wearing for 2 weeks
Wow, so masks are effective right? WRONG
Confounders/Problems with the data
1.) This study was done during Delta, and doesn't take into account the substantial increase in transmission from Omicron that would likely change the figures in this study if it were done in the current atmosphere. In other words, applying Delta data to Omicron is inappropriate.
2.) The effect size is too large. For example, if cloth masking really reduced the risk of a positive test/infection by over 50%, the pandemic would have been over by now.
3.) The rate of response in both groups was too low. Of 11,387 positive and 17,051 negative test cases, only 13.4% and 8.8% respectively picked up the phone an engaged in the study. This has bias written all over it. Who are the kinds of people picking up the phone? Are the test negatives more neurotic and apt to pick up? Are positives too sick to pick up?
4.) Masking was self reported. For that reason there were surely inaccurate reports. Also, there is shame in saying you didn’t wear a mask for some. For those reasons self reporting was likely confounded.
5.) There were only 652 participants in the positive arm, and 1,176 participants in the control arm of the study from 9 counties in California. That said, the trial is too under powered so figures from data are unlikely to represent the vast and diverse population of the United States.
6.) "This analysis does not account for potential differences in the intensity of exposures, which could vary by duration, ventilation system, and activity in each of the various indoor public settings visited”. In other words context matters. Being in a restaurant near 10 people poses a different risk compared to a close packed concert with 15 thousand people.
7.) Study didn’t control for equal vaccination status between the two groups (the 652 who tested positive, and 1,176 that were negative) which has a strong impact on whether or not someone will test positive or not. For instance 78.4% of positive tests were unvaccinated while 57.5% in the control arm did not test positive.
8.) Interviewers were not blinded and knew who did and didn't test positive, that creates bias in the study.
9.) “Participants who indicated typically wearing multiple different mask types were categorized as wearing either a cloth mask (if they reported cloth mask use) or a surgical mask (if they did not report cloth mask use)”. Not being able to differentiate can’t give you a true figure on how cloth, and surgical masks actually lowered the odds of testing positive.
10.) Worst of all, in this study CDC reports that “wearing a cloth mask compared to not wearing a mask WAS NOT STATISTICALLY SIGNIFICANT”, yet odds of testing positive were 56% lower. Confusing, I know, i’ll explain.
That means, even though the study, and picture below indicate 56% lowered odds of testing positive if wearing a cloth mask, the benefit of that 56% is derived from other more trivial numbers.
It’s like saying there’s a drug that provided a relative risk reduction of 50% against heart attack. However, if you look deeper you’d find the figure comes from another more salient data point showing that heart attack with the drug went from 1% down to 0.5% overall. Yes 1 down to 0.5 is a 50% drop, but the numbers were changed to make it look more important than it actually was. The risk already low to begin with.
Same thing here except CDC directly admits cloth masks are insignificant. That means all other masks are ineffective as well, but just a little more protective than the cloth mask.
So what’s the takeaway?
The only thing that can be concluded from this study is that the CDC continues to put out questionable data. The truth is, all data needs to be reviewed. Sadly, when encountering work like this it can make one lose faith in the agency releasing it. Cloth masks reducing infection by over 50%? Surely they jest.
LETS CONNECT:
To think that you can prevent a disease like covid from spreading is stupid and that has been the common denominator behind agencies' responses globally: stupidity. The world has been taken over by stupid; who could have imagined that?