Using child reported respiratory symptoms to diagnose asthma in the community.
OBJECTIVE
To study how respiratory symptoms reported by children, with or without spirometry, could help to discriminate those with asthma from those without.


METHODS
Respiratory symptoms (frequent cough, frequent phlegm, and wheezing) reported by 1646 schoolchildren (aged 8-12 years) in a respiratory questionnaire and the FEV1:FVC ratio measured with spirometry (at three different cut-off values of 0.70, 0.75, and 0.80) were compared against the criterion standard of a physician diagnosis of asthma reported by the parents.


RESULTS
The overall prevalence of asthma was 6%; more boys had asthma. Wheezing had the best discriminating ability among the three symptoms and a cut-off point at 75% was best for the FEV1:FVC ratio. Combining wheezing with an FEV1:FVC ratio <75% gave the highest discriminating ability of 83%. If the tests were applied to hypothetical populations with higher prevalence ratios of asthma, the added value of the FEV1:FVC ratio became less apparent.


CONCLUSIONS
Respiratory symptoms, especially wheezing, reported by children had good discriminating ability for asthma and could be adopted for opportunistic screening in the primary care settings.
Yu
I T S
IT
Department of Community & Family Medicine, The Chinese University of Hong Kong, School of Public Health, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China. iyu@cuhk.edu.hk
Wong
T W
TW
Li
W
W
D001249:Asthma / Q000175:diagnosis* / Q000503:physiopathology; D002648:Child; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012135:Respiratory Sounds / Q000175:diagnosis* / Q000503:physiopathology; D012650:Self Disclosure; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires; D014797:Vital Capacity / Q000502:physiology