Figure 1. Flowchart for identification of studies.
A: The number of studies that provided usable data on knowledge scores (A1) and skill scores (A2).
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.