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. 2021 Mar 16;21:120. doi: 10.1186/s12876-021-01704-w

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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/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

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Fig. 1 — Study selection process: Overall, a total of 3277 articles were identified using the above mentioned search strategy from the pre-specified databases. 1577 studies were removed as duplicates and the remaining 1700 studies were screened using the pre-specified inclusion and exclusion criteria. After title and abstract screening, 1545 studies were deemed irrelevant, and the remaining 155 articles were reviewed by full-text. 15 studies were selected for inclusion of the systematic review. Additional 9 articles/product monographs were identified outside of the search strategy and included for the review