Flow diagram of the study selection process.

<p><i>From</i>: Moher D, Liberati A, Tetzlaff J, Altman DG, The PRISMA Group (2009). <i>P</i>referred <i>R</i>eporting <i>I</i>tems for Systematic Reviews and <i>M</i>eta-<i>A</i>nalyses: The PRISMA Statement. PLoS Med 6(7): e1000097. doi: <a href="https://doi.org/10.1371/journal.pmed1000097" target="_blank">10.1371/journal.pmed1000097</a><b>For more information</b>, <b>visit</b><a href="http://www.prisma-statement.org" target="_blank">www.prisma-statement.org</a>.