Clinical progression in 83 children followed from inclusion to 9 years of age.

<p>At each evaluation, children were divided into symptomatic (gray part of bars) and asymptomatic (black part of bars). Each bar represents 100% of children who completed the study (n = 83). Twenty-nine percent of children were classified as symptomatic at 5 years, 7 years, and 9 years, and were classified as persistent wheezers. Forty-six percent of children were intermittently classified as symptomatic (intermittent wheezers), and 25% of children were classified as asymptomatic at all three evaluations (asymptomatic children).