Figure 1. PRISMA flow diagram of the study identification, inclusion, and exclusion.
A total of 89 non-duplicate records were identified, and finally, seven RCTs were included for the meta-analysis.
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.