Figure 1.
The study selection process based on the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses. 2020 statement. China National Knowledge Infrastructure (CNKI).
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.