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.
Comparison of rates of COPD exacerbations in person-years between participants with IgG subclass deficiency and normal IgG subclass levels in the merged dataset (MACRO and STATCOPE cohorts combined, n = 1629). Error bars represent 95% confidence interval
