Figure 2. Study flowchart.
In this figure, we present the numbers of observations included in analyses in the different subsections of the Results section.
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.