>Free mask distribution and promotion reduced the proportion of people who reported COVID-like symptoms on average by 11 percent, which was driven mainly by the effects of surgical masks. Villages where cloth masks were distributed experienced a 5 percent reduction in symptoms, while villages where surgical masks were distributed saw a reduction of 12 percent. About a third (40 percent) of those who reported COVID-19 symptoms agreed to have their blood tested for SARS-CoV-2. On average, researchers found a decrease of symptomatic SARS-CoV-2 infections of 9 percent. This reduction was higher in villages that wore a surgical mask (11 percent) and in these, among individuals aged 60+ (35 percent).

It is measuring the effectiveness of the public policy and comparing how it differs when the masks distributed were cloth versus surgical. There is nothing in this report about the effectiveness of masks on an individual level.