PURPOSE: The prevalence of asthma symptoms among preschool children is difficult to determine with accuracy because no gold standard is available for diagnosis. The aim of this study was to compare parent-reported wheezing or shortness of breath among infants as assessed by questionnaire and physician-interview.
METHODS: We studied 1,202 children participating in the Generation R study. Their parents completed a written questionnaire at home when the infant was 12 months old, including items on wheezing or shortness of breath. During the regular free-of-charge youth healthcare visit at age 14 months, the physician interviewed the parents to assess the presence of wheezing or shortness of breath.
RESULTS: The prevalence of wheezing or shortness of breath estimated from questionnaire was significantly higher than from physician-interview (36% vs. 20%; P < 0.001): observed agreement 73% (kappa 0.36). Only 41% of questionnaire-reported symptoms were assessed through the physician-interview, while 73% of physician-interviewed symptoms were reported in the questionnaire. Compared with infants in the subgroup with agreement on the presence of wheezing or shortness of breath, the infants in the subgroups without agreement significantly less often received anti-asthma medication and significantly less often had abnormal respiratory sounds or bronchiolitis or croup, and their mothers were significantly less often working. The proportion of infants receiving anti-asthma medication was higher in interview-data compared with questionnaire-data (22.7% vs. 3.9%; P < 0.001).
CONCLUSIONS: Questionnaire yielded higher prevalence rates for wheezing or shortness of breath than physician-interview. Physician-reported symptoms are associated with a higher proportion of infants receiving anti-asthma medication. Parent-reported asthma symptoms should be confirmed by pediatricians whenever possible.