New Mask Study
Medical Masks Versus N95 Respirators for Preventing COVID-19 Among Health Care Workers. https://doi.org/10.7326/M22-1966
Professor Carl Heneghan of the Centre for Evidence Based Medicine at Oxford University has just tweeted the results of a sizeable multicentre randomised trial into mask effectiveness (29 centres, 1009 subjects). I noted that they'd done something sensible and that is to compare performance of ear loop masks (a.k.a. surgical masks) with full-on N95 respi…