title: Prevalence of childhood atopic dermatitis: an urban and rural community-based study in Shanghai, China.
abstract: BACKGROUND
  Atopic dermatitis (AD) is a common inflammatory and chronically relapsing disorder with increasing prevalence. However, little is known about its prevalence in Shanghai, the top metropolitan of China. This study will estimate and compare the prevalence of AD in urban and rural areas in representative samples of 3 to 6-year-old children in Shanghai.
  
  
  RESULTS
  A descriptive cross-sectional study was performed. Pre-school children were obtained by cluster sampling from 8 communities in different districts in Shanghai. The main instrument was the core questionnaire module for AD used in the U.K. Working Party's study. All the data were statistically analyzed by EpiData 3.1 and SPSS16.0. A total of 10,436 children completed the study satisfactorily, with a response rate of 95.8%. The prevalence of AD in 3 to 6-year-old children was 8.3% (Male: 8.5%, Female: 8.2%). The prevalence in urban areas of Shanghai was gradiently and significantly higher than that in rural areas. The highest prevalence was in the core urban area (10.2% in Xuhui Tianping) vs. the lowest far from the urban areas (4.6% in Chongming Baozhen).
  
  
  CONCLUSIONS
  The prevalence of AD was 8.3% (95%CI: 7.6%-9.1%) in children aged 3 to 6 in Shanghai. The prevalence of AD decreased from the center to the rural areas in Shanghai.
authors.affiliation: Department of Dermatology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Xu
authors.forename: Shuxian
authors.initials: S
authors.lastname: Yan
authors.forename: Fei
authors.initials: F
authors.lastname: Li
authors.forename: Minqiang
authors.initials: M
authors.lastname: Cai
authors.forename: Weihan
authors.initials: W
authors.lastname: Chai
authors.forename: Minmin
authors.initials: M
authors.lastname: Wu
authors.forename: Chaowei
authors.initials: C
authors.lastname: Fu
authors.forename: Zhuohui
authors.initials: Z
authors.lastname: Zhao
authors.forename: Haidong
authors.initials: H
authors.lastname: Kan
authors.forename: Kefei
authors.initials: K
authors.lastname: Kang
authors.forename: Jinhua
authors.initials: J
authors.lastname: Xu
mesh_terms: D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D003876:Dermatitis, Atopic / Q000453:epidemiology*; D005260:Female; D005843:Geography; D006801:Humans; D007223:Infant; D008297:Male; D015995:Prevalence; D012423:Rural Health / Q000706:statistics & numerical data; D012424:Rural Population / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires; D014504:Urban Health / Q000706:statistics & numerical data; D014505:Urban Population / Q000706:statistics & numerical data*