An analysis of studies pertaining to masks in Morbidity and Mortality Weekly Report: Characteristics and quality of studies from 1978 to 2023 – PubMed
MMWR publications pertaining to masks drew positive conclusions about mask effectiveness >75% of the time despite only 30% testing masks and <15% having statistically significant results. No studies were randomized, yet over half drew causal conclusions. The level of evidence generated was low …