Study Screening and Selection
Two investigators independently examined the titles and abstracts of the
search results using the predefined inclusion criteria. For all titles
that appear to meet the inclusion criteria or those where there was some
uncertainty, full text was accessed. The two reviewers assessed whether
the articles met the selection criteria. Any disagreements were resolved
by discussion or arbitration from a third reviewer. Reasons for
excluding studies were recorded and is available at supplemental
material.