An official website of the United States government
Here's how you know
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.
Cochrane risk-of-bias summary: the authors' judgments about the studies. Studies included within the systematic review mostly ranged from low risk to some concerns except for one high-risk study per the risk-of-bias assessment.