Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
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A lock (
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connected to the .gov website. Share sensitive
information only on official, secure websites.
Risk of bias graph. Green for negligible risk of bias, yellow for unclear risk of bias, and red for substantial risk of bias. Shows the overall risk of bias for each domain. For example, the length of the green rectangle means the number of studies assessed as minimal risk of bias.
