Figure 1.
Stages involved in selecting published data for inclusions in the current study are depicted in a flow chart; n: number of literature reports.
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.