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. 2021 Mar 23;7(3):303–313. doi: 10.1016/j.sleh.2021.02.008

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© 2021 Published by Elsevier Inc. on behalf of National Sleep Foundation.

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Fig 2 — Monthly average bedtime variability (assessed as standard deviation) from 2018 to 2020, averaged across all age groups and cities. Average sleep duration increased across all these cities during March and April 2020, while it decreased during the same time in the previous years. Bands represent 95% confidence interval when averaged over cities.