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Flow chart showing the meta-analysis studies selection.
A total of 1980 studies were identified, and 1213 studies were excluded because of duplication. After reading the titles and abstracts, 608 studies were excluded. 159 possible full text studies were carefully reviewed (no data for 0 h. [n = 35]; animal studies [n = 24]; review and meta-analysis [n = 11]). Finally, 89 trials were included for quantitative analysis.
