The most rigorous and comprehensive analysis of scientific studies conducted on the efficacy of masks for reducing the spread of respiratory illnesses " including Covid-19 " was published late last month. Its conclusions, said Tom Jefferson, the Oxford epidemiologist who is its lead author, were unambiguous. "There is just no evidence that they" " masks " "make any difference," he told the journalist Maryanne Demasi. "Full stop." But, wait, hold on. What about N-95 masks, as opposed to lower-quality surgical or cloth masks? "Makes no difference " none of it," said Jefferson. These observations don't come from just anywhere. Jefferson and 11 colleagues conducted the study for Cochrane, a British nonprofit that is widely considered the gold standard for its reviews of health care data. The conclusions were based on 78 randomized controlled trials, six of them during the Covid pandemic, with a total of 610,872 participants in multiple countries. And they track what has been widely observed in the United States: States with mask mandates fared no better against Covid than those without. People may have good personal reasons to wear masks, and they may have the discipline to wear them consistently. Their choices are their own. But when it comes to the population-level benefits of masking, the verdict is in: Mask mandates were a bust. The mainstream experts and pundits who supported mandates were wrong.