Figure 2.
Threshold to consider use of mucus clearance devices for chronic obstructive pulmonary disease (COPD) management (n=1188).
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.