and masking works

 ...go figure.

A new report released this week in the New England Journal of Medicine effectively used DESE's rescinding the mask requirement as an experiment: when that happened, many districts stopped requiring masks, but Boston and Chelsea didn't. The researchers looked at:

The final sample included 72 school districts, which comprised 294,084 students and 46,530 staff during the study period. The study period was defined as the 40 calendar weeks of the 2021–2022 school year, which ended on June 15, 2022 (the end of the last full reporting week in all districts).

And what did they find?

Before the statewide masking policy was rescinded, the trends in the incidence of Covid-19 observed in the Boston and Chelsea districts were similar to the trends in school districts that later lifted masking requirements. However, after the statewide masking policy was rescinded, the trends in the incidence of Covid-19 diverged, with a substantially higher incidence observed in school districts that lifted masking requirements than in school districts that sustained masking requirements. 

Specifically: 

 Overall, the lifting of masking requirements was associated with an additional 44.9 Covid-19 cases per 1000 students and staff (95% CI, 32.6 to 57.1) during the 15 weeks after the statewide masking policy was rescinded 

An editorial accompanying the research relates this to the massively inequitable costs of COVID. You can also find coverage on WGBH, The New York Times, The Washington Post.

And from one of the Twitter education satire accounts:

Point: New Study Finds Evidence That Mask Mandates in Schools Work

Counterpoint: Masks Give Some Anti-Vax/Anti-Mask Doctors and Politicians Bad Vibes and Heebie-Jeebies https://t.co/X7DeZ6c87D

— New York Times Education Pitchbot (@GreyLadiesNYC) November 10, 2022