Marginal Revolution described a sneering critique of "one of the worst studies i've ever seen in any field" as "Overstated, unreasonable, and too polemic" and your sober expression of reservations is a lot easier on the eyes.
But polemic does not mean wrong, and the author makes some valid points:
· Medpage Today observes that "The primary endpoint was reporting symptoms consistent with COVID-19 followed by a positive serology test to document SARS-CoV-2 infection." But this measure (aside from the unreliability of self-reported symptoms, and more than half the people with symptoms refusing the blood test) was not taken at the beginning of the study, so the before-and-after situation is open to interpretation.
· When the study was mentioned in the Washington Post, it pointed out that "the intervention group was found to practice more social distancing, which may complicate the findings on masks." There were many other consequences of the interventions, but masks were given primary credit, with the usual hyperbolic headline stating "Massive randomized study is proof that surgical masks limit coronavirus spread".
I understand choosing Bangladesh because of how relatively inexpensive it is to pay people there
"Randomization of treated villages to no incentive, monetary incentive of 190 USD, or nonmonetary incentive. We announced that the monetary reward or the certificate would be awarded if village-level mask wearing among adults exceeded 75% 8-weeks after the intervention started."
So some villages had something to lose if they didn't please the researchers.
Has the spread of influenza-like illness changed so much since 2019 that we can't rely on the WHO's review of the evidence?