Rigorous research
The study took place over a period of 8 weeks in each district. The interventions were rolled out in waves, with the first starting in November 2020 and the last in January 2021.
Investigators gave each household free cloth or surgical face masks and showed families a video about proper mask wearing with promotional messages from the prime minister, a head imam, and a national cricket star. They also handed out free masks.
Previous studies have shown that people aren’t always truthful about wearing masks in public. In Kenya, for example, 88% of people answering a phone survey said that they wore masks regularly, but researchers determined that only 10% of them actually did so.
Investigators in the Bangladesh study didn’t just ask people if they’d worn masks, they stationed themselves in public markets, mosques, tea stalls, and on roads that were the main entrances to the villages and took notes.
They also tested various ways to educate people and to remind them to wear masks. They found that four factors were effective at promoting the wearing of masks, and they gave them an acronym – NORM.
- N for no-cost masks.
- O for offering information through the video and local leaders.
- R for regular reminders to people by investigators who stand in public markets and offer masks or encourage anyone who wasn’t wearing one or wasn’t wearing it correctly.
- M for modeling, in which local leaders, such as imams, wear masks and remind their followers to wear them.
These four measures tripled the wearing of masks in the intervention communities, from a baseline level of 13% to 42%. People continued to wear their masks properly for about 2 weeks after the study ended, indicating that they’d gotten used to wearing them.
Dr. Styczynski said that nothing else – not text message reminders, or signs posted in public places, or local incentives – moved the needle on mask wearing.
Saved lives and money
The study found that the strategy was cost effective, too. Giving masks to a large population and getting people to use them costs about $10,000 per life saved from COVID, on par with the cost of deploying mosquito nets to save people from malaria, Dr. Styczynski said.
“I think that what we’ve been able to show is that this is a really important tool to be used globally, especially as countries have delays in getting access to vaccines and rolling them out,” she said.
Dr. Styczynski said masks will continue to be important even in countries such as the United States, where vaccines aren’t stopping transmission 100% and there are still large portions of the population who are unvaccinated, such as children.
“If we want to reduce COVID-19 here, it’s really important that we consider the ongoing utility of masks, in addition to vaccines, and not really thinking of them as one or the other,” she said.
The study was funded by a grant from GiveWell.org. The funder had no role in the study design, interpretation, or the decision to publish.
A version of this article first appeared on Medscape.com.