Objective: To understand the prevalence rate,pathogenesis and risk factors of asthma in children aged 0 ~ 14 in Nanming district,Guiyang city. Methods: A total of 10 610 samples were randomly selected from 16 survey sites in Nanming district of Guiyang city including communities,kindergartens and middle schools by cluster sampling. The number of children with asthma was confirmed by questionnaire survey combined with physical examination,and a control study was conducted with asthmatic children as the case ...