FIGURE 1.
Receiver-operating characteristic curve. Area under curve = 0.638 (95% confidence interval, 0.571–0.705), P < 0.001.
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.