Data collected in preschool and school age
At the follow-up visit one year after the index episode requiring
hospitalization, asthma was diagnosed if at least three episodes of
physician-confirmed wheezing during the preceding year were
reported.14 In 1995, at a median age of 4.0 years,
asthma was defined as the presence of a previous asthma diagnosis and at
least one reported physician-diagnosed wheezing episode during the
preceding year or reported use of maintenance medication for
asthma.15 In 1999 and 2004, at median ages of 7.2 and
12.3 years, respectively, asthma was diagnosed if continuous maintenance
medication for asthma, or repeated wheezing episodes and/or a prolonged
cough apart from the infection during the preceding 12 months were
reported, and the result of an exercise challenge test was
positive.12,16