Fig 2. Kaplan-Meier plots illustrating the survival function of time to first URTI among all the subjects and stratified by sex.
The shaded area is the (pointwise) 95% confidence interval. Abbreviations: URTI = upper respiratory tract infections.
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.