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. 2023 Jun 28. Online ahead of print. doi: 10.1016/j.jagp.2023.06.012

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© 2023 Published by Elsevier Inc. on behalf of American Association for Geriatric Psychiatry.

Since January 2020 Elsevier has created a COVID-19 resource centre with free information in English and Mandarin on the novel coronavirus COVID-19. The COVID-19 resource centre is hosted on Elsevier Connect, the company's public news and information website. Elsevier hereby grants permission to make all its COVID-19-related research that is available on the COVID-19 resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. These permissions are granted for free by Elsevier for as long as the COVID-19 resource centre remains active.

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Nurses Health Study II (NHSII) COVID-Substudy participant flowchart (A) and timeline (B)

Note: NHS: Nurses Health Study; Quotation marks in panel B detail the abbreviated naming system that appears throughout the manuscript to index study waves.