Abstract
OBJECTIVES: In epidemiological studies, childhood asthma is usually assessed with questionnaires directed at parents or children, and these may give different answers. We studied how well parents and children agreed when asked to report symptoms of wheeze and investigated whose answers were closer to measurable traits of asthma. METHODS: LuftiBus in the school is a cross-sectional survey of respiratory health among Swiss schoolchildren aged 6-17 years. We applied questionnaires to parents and children asking about wheeze and exertional wheeze in the past year. We assessed agreement between parent-child answers with Cohen's kappa (k), and associations of answers from children and parents with fractional exhaled nitric oxide (FeNO) and forced expiratory volume in 1 s over forced vital capacity (FEV(1) /FVC), using quantile regression. RESULTS: We received questionnaires from 3079 children and their parents. Agreement was poor for reported wheeze (k = 0.37) and exertional wheeze (k = 0.36). Median FeNO varied when wheeze was reported by children (19 ppb, interquartile range [IQR]: 9-44), parents (22 ppb, IQR: 12-46), both (31 ppb, IQR: 16-55), or neither (11 ppb, IQR: 7-19). Median absolute FEV(1) /FVC was the same when wheeze was reported by children (84%, IQR: 78-89) and by parents (84%, IQR: 78-89), lower when reported by both (82%, IQR: 78-87), and higher when reported by neither (87%, IQR: 82-91). For exertional wheeze findings were similar. Results did not differ by age or sex. CONCLUSION: Our findings suggest that surveying both parents and children and combining their responses can help us to better identify children with measurable asthma traits.