Figure 6.
Duration of the operation. CIs: Confidence intervals, RCTs: Randomised controlled trials, SD: Standard deviation, df: Degree of freedom, IV: Inverse variance
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.