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. 2023 Aug 4;11:1180694. doi: 10.3389/fped.2023.1180694

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© 2023 Bu, Liu, Shahjalal, Zheng, Liu, Ye, Xu, Peng, Wang, Chen, Liu, Liu and Liu.

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A flowchart of study screening and selection. CNKI, China national knowledge infrastructure; SinoMed, the Chinese biomedical literature database; WanFang, the WanFang database; VIP, the Chinese scientific journals full-text database.