Figure 4.
Begg's funnel plots for publication bias test. (A) *0201; (B) *0301; (C) *0502; (D) *0303 and (E) *0604.
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.