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. 2021 Nov 4;60(1):3–12. doi: 10.1097/MLR.0000000000001654

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Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.

This article is made available via the PMC Open Access Subset for unrestricted re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the COVID-19 pandemic or until permissions are revoked in writing. Upon expiration of these permissions, PMC is granted a perpetual license to make this article available via PMC and Europe PMC, consistent with existing copyright protections.

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Flow diagram of the final analytic sample with inclusion and exclusion criteria. COVID-19 indicates coronavirus disease 2019; NC, North Carolina; SC, South Carolina.