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. 2021 Dec 17;35(1):163–186. doi: 10.1007/s10334-021-00985-2

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© The Author(s) 2021

Open AccessThis 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 licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence 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 licence, visit http://creativecommons.org/licenses/by/4.0/.

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Fig. 1 — Workflow of the study search and selection. Two databases were searched using the predefined search strategy—MEDLINE, Medical Literature Analysis and Retrieval System Online (PubMed), and Web of Science database (WoS). After excluding the duplicates the studies were initially screened by title (excluding n = 446 studies), abstract (excluding n = 96 studies), and full text (excluding n = 25 studies), leaving 60 studies. Six more studies were discovered by screening the reference sections of selected studies