The diagnosis of allergic rhinitis was established by history, physical examination, and skin testing for immediate hypersensitivity to airborne allergens.

In addition, allergen-specific IgE concentrations of food and airborne allergens were measured in blood samples collected at age 8 y.

About 10 million U.S. residents have so-called allergic asthma, in which asthma attacks are triggered by pollen or other airborne allergens.

At 4 years, the response rate was 90%, and allergen-specific IgE levels to food and airborne allergens were measured in 2614 of the participating children.