Figure 1.
QUOROM (for 'Quality of Reporting of Meta-analyses' using standards developed by the QUOROM group) flow diagram, summarizing study selection for inclusion.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.