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.
Includes children younger than 6 years. Data are from the Norwegian Prescription Database from January 1, 2009, through December 31, 2014. Error bars indicate 95% CI.
