Who knew, apparently masks work in real life: https://www.poverty-action.org/sites...ity_083121.pdf

Here is RCT pre-registration: https://clinicaltrials.gov/ct2/show/NCT04630054

Here is WP summary: https://www.washingtonpost.com/world...id-bangladesh/

Also just an impressive piece of work by a set of talented economists. This is not peer-reviewed yet but knowing the authors I doubt they screwed up. I hope Science will publish it.