title: Prevalence of atopic dermatitis in Japanese elementary schoolchildren.
abstract: BACKGROUND
  Although there have been several reports on the prevalence of atopic dermatitis (AD) in Japanese schoolchildren based on questionnaires, there has been no nation-wide study of the frequency of this condition diagnosed by dermatologists in regular health check-ups of schoolchildren.
  
  
  OBJECTIVE
  The objective of this work was to evaluate precisely the prevalence of AD in elementary schoolchildren in Japan based on regular health check-ups by dermatologists.
  
  
  METHODS
  In 2001/2, elementary schoolchildren: first graders (age 6-7 years) and sixth graders (age 11-12 years) were examined by dermatologists in eight prefectures of Japan (Hokkaido, Iwate, Tokyo, Gifu, Osaka, Hiroshima, Kochi and Fukuoka). In each prefecture, public elementary schools were randomly selected from urban and rural districts. We planned to examine about 700 schoolchildren in each of urban first, urban sixth, rural first and rural sixth grades from the eight areas, a total of 22 400 children (700 x 4 x 8). AD was diagnosed by the dermatologists based on the Japanese Dermatological Association criteria for the disease.
  
  
  RESULTS
  The point prevalence of AD was 11.2% overall (2664 of 23 719) ranging from 7.4% (Iwate) to 15.0% (Fukuoka) in the eight areas. Seventy-four per cent, 24%, 1.6% and 0.3% of those afflicted were in the mild, moderate, severe and very severe groups, respectively. Overall, the prevalence of first graders was slightly higher than that of sixth graders (11.8% vs. 10.5%, P < 0.01). There was no apparent difference in prevalence between urban and rural districts, or between boys and girls.
  
  
  CONCLUSIONS
  The prevalence of AD in Japanese elementary schoolchildren was about 10%, three-quarters of those being mildly affected. This is the first nation-wide study made of Japanese elementary schoolchildren examined by dermatologists to evaluate the frequency of AD.
authors.affiliation: Department of Dermatology, Faculty of Medicine, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8655, Japan. SAEKI-DER@h.u-tokyo.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Saeki
authors.forename: H
authors.initials: H
authors.lastname: Iizuka
authors.forename: Y
authors.initials: Y
authors.lastname: Mori
authors.forename: T
authors.initials: T
authors.lastname: Akasaka
authors.forename: H
authors.initials: H
authors.lastname: Takagi
authors.forename: Y
authors.initials: Y
authors.lastname: Kitajima
authors.forename: T
authors.initials: T
authors.lastname: Tezuka
authors.forename: T
authors.initials: T
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Hide
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Y
authors.initials: Y
authors.lastname: Hirose
authors.forename: H
authors.initials: H
authors.lastname: Kodama
authors.forename: K
authors.initials: K
authors.lastname: Urabe
authors.forename: M
authors.initials: M
authors.lastname: Furue
authors.forename: F
authors.initials: F
authors.lastname: Kasagi
authors.forename: H
authors.initials: H
authors.lastname: Torii
authors.forename: K
authors.initials: K
authors.lastname: Nakamura
authors.forename: E
authors.initials: E
authors.lastname: Morita
authors.forename: Y
authors.initials: Y
authors.lastname: Tsunemi
authors.forename: K
authors.initials: K
authors.lastname: Tamaki
mesh_terms: D002648:Child; D003876:Dermatitis, Atopic / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D010808:Physical Examination; D015995:Prevalence; D012572:School Health Services; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires