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.
Differences in rate of change of prevalence of current rhinoconjunctivitis, comparing trends after ISAAC Phase III with those before ISAAC Phase III among centres with data at three time points, by age group and centre
Results expressed as absolute percentage change per 10 years.
