Researchers from Stanford, Yale, the Bangladeshi nonprofit GreenVoice and the research group Innovations for Poverty Action, among others, are conducting an ongoing study in 600 villages in Bangladesh to figure out the most effective [techniques to encourage mask-wearing], with the goal of sharing them across the globe.
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The researchers randomly chose 300 villages to receive mask interventions for eight weeks. Another 300 villages received no intervention at all — they’d be the comparison group.
The strategies essentially centered on free face coverings and reminders. Each household got three free masks, but people could also get free masks at mosques or markets. People were shown videos of notable Bangladeshis, such as national cricket star Shakib Al Hasan or Prime Minister Sheikh Hasina, discussing how and when to wear the face coverings.
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[Yale professor Mushfiq] Mobarak and his team were surprised by what they found. The core interventions — which included the free masks and frequent reminders — more than tripled mask use, from 13% in the comparison villages to 42% in the treatment villages.
Furthermore, people kept wearing masks after the volunteer promoters of masks left the villages. “Even after 10 weeks, after we finished everything, the mask-wearing persisted. That’s what got us excited,” Mobarak says.