## Mask Mandates Save Lives

_IMF Working Papers, August 6, 2021_

## Source details

**Canonical URL:** [Mask Mandates Save Lives](https://www.imf.org/en/publications/wp/issues/2021/08/05/mask-mandates-save-lives-460123)

## Other formats

- [Markdown version](/en/publications/wp/issues/2021/08/05/mask-mandates-save-lives-460123/index.md)
- [Structured JSON version](/en/publications/wp/issues/2021/08/05/mask-mandates-save-lives-460123/index.json)
- [Bundle manifest](/en/publications/wp/issues/2021/08/05/mask-mandates-save-lives-460123/bundle-manifest.json)

## Bibliographic details
- Authors: Niels-Jakob H Hansen, Rui Mano
- Published: August 6, 2021
- Series: IMF Working Papers
- DOI: https://doi.org/10.5089/9781513577616.001

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### Summary and research question
- Quantifies the effect of mask mandates in the United States using a regression discontinuity design exploiting county-level variation across state borders with and without mandates.
- Focuses on outcomes: COVID-19 cases, hospital admissions, and deaths.

### Methods
- Regression discontinuity design at county borders between states with and without mask mandates.
- County-level variation used for cases, hospital admissions, and deaths.

### Key quantitative findings
- Mask mandates reduced new weekly COVID-19 cases by 55 per 100,000 inhabitants on average.
- Mask mandates reduced new weekly hospital admissions by 11 per 100,000 inhabitants on average.
- Mask mandates reduced new weekly deaths by 0.7 per 100,000 inhabitants on average.
- Estimated lives saved through December 19, 2020: 87,000.
- Estimated additional lives that could have been saved under a nationwide mandate: 58,000.

### Heterogeneity and behavioral interaction
- The effect of mask mandates depends on attitudes toward mask wearing at the county level.
- Larger effects observed in counties more positively inclined towards mask wearing.

### Policy implications
- Mask mandates are a crucial tool to counter pandemics when widely accepted by the population.
- Findings are relevant for countries unable to immunize large swaths of their population in the short term.

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## Content in this bundle

- **Working Paper**
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  - [Working Paper (PDF)](/-/media/files/publications/wp/2021/english/wpiea2021205-print-pdf.pdf){rel="external" type="application/pdf"}

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_Source: https://www.imf.org/en/publications/wp/issues/2021/08/05/mask-mandates-save-lives-460123_