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. 2022 Oct 4;9:600. doi: 10.1038/s41597-022-01704-9

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© The Author(s) 2022

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 — PRISMA flowchart. Highlighted are the different databases used, the number of studies included at each stage of the screening, and the reasons for excluding studies. *The five studies found during non-systematic searches include two studies found during pilot searches in Google, and three studies mistakenly excluded during the screening, but included in a previous synthesis by Rohr and colleagues¹⁶.