Table 5.

Secondary and exploratory outcome variables.

Secondary outcomes:
Annualized number of days with: any respiratory symptoms (wheezing, cough, or shortness of breath), or albuterol use.
Rate of oral corticosteroid courses.
Rate of antibiotic courses.
Rates of drug related side effects and severe adverse reactions*.
Time to parent-reported asthma diagnosis OR to the third episode of wheezing.
Time to parent-reported physician asthma diagnosis.
Exploratory outcomes:
Annualized number of days with wheezing, and of days with nighttime awakening due to respiratory symptoms.
Cumulative number of wheezing episodes.
Annualized number of days with parental absence from work due to child's respiratory symptoms, and days with child absence from day-care.
Proportion of children prescribed asthma controller medications (ICS, LTRA).
Proportion of children with at least one positive serum specific IgE (SIgE) to inhalant allergen.
Rates of ED and urgent care visits, and of hospitalizations for respiratory symptoms.
Rates of upper respiratory tract infections.
Time to the fourth wheezing episode.
Total IgE level and eosinophil count**.

ED: emergency department, ICS: inhaled corticosteroids; LTRA: leukotriene receptor antagonist.

* The monitoring of potential drug related side effects starts immediately after randomization. The time frame for measurement of all other long-term outcomes starts at the end of the treatment period (2 weeks from randomization) and ends at the end of the follow-up period.