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. 2023 Dec 20;3:188. doi: 10.1038/s43856-023-00423-5

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© The Author(s) 2023

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

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Fig. 1 — The flow of persons from receiving their questionnaire (n = 294,035) to inclusion in the final study populations (n = 88,818). Persons were exluded if they did not respond fully to their questionnaire. Of those that filled out the questionnaire (n = 106,117), persons above 65 years of age, persons with a seropositive result for COVID-19, and persons who received a questionnaire with an error were excluded.