Prevalence of wheeze and other respiratory symptoms (white children).

<p>*A few questionnaire items had different wording in the two groups. Among them was the question about wheeze ever: Attack group: "Has your child ever had attacks of wheezing?"; Whistling group: "Has your child ever had wheezing or whistling in the chest at any time in the past?" Based on this, the groups were labeled "attack group" and "whistling group".</p><p>^† Chi squared tests</p><p>Prevalence of wheeze and other respiratory symptoms (white children).