title: Time spent outdoors at midday and children's body mass index.
abstract: OBJECTIVE
  We investigated whether the Kidskin sun protection intervention increased children's body mass index by reducing the time spent outdoors at midday.
  
  
  METHODS
  The Kidskin sun protection intervention involved 1614 Australian school children assigned to 1 of 3 groups: a control group, a moderate-intervention group, or a high-intervention group. Schools in the control group received the standard health curriculum and schools in the intervention groups received a multicomponent intervention. Outcomes included time spent outdoors and nevus development (a marker of melanoma risk). Height and weight were measured at 3 time points. Body mass index was transformed into age- and gender-specific z scores; z scores at each age were modeled simultaneously. Time spent outdoors at ages 10 and 12 years was analyzed using a linear mixed effects modeling.
  
  
  RESULTS
  The proportion of children who were overweight or obese increased with age. The moderate-intervention and control groups had a minimal increase in z score over time, and the z score for the high-intervention group decreased over time. There were no differences among groups with respect to total time outdoors at any age.
  
  
  CONCLUSIONS
  It is possible to reduce the time children spend outdoors when ultraviolet radiation is high without producing an unfavorable effect on the children's body mass index.
authors.affiliation: Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, West Perth. lizm@ichr.uwa.edu.au
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Milne
authors.forename: Julie A
authors.initials: JA
authors.lastname: Simpson
authors.forename: Robyn
authors.initials: R
authors.lastname: Johnston
authors.forename: Billie
authors.initials: B
authors.lastname: Giles-Corti
authors.forename: Dallas R
authors.initials: DR
authors.lastname: English
mesh_terms: D015992:Body Mass Index; D002648:Child; D003479:Curriculum; D005260:Female; D006266:Health Education / Q000379:methods*; D006801:Humans; D008297:Male; D008545:Melanoma / Q000209:etiology / Q000517:prevention & control; D009043:Motor Activity; D009765:Obesity / Q000453:epidemiology / Q000517:prevention & control*; D017063:Outcome Assessment, Health Care; D015397:Program Evaluation; D011998:Recreation; D018570:Risk Assessment; D012307:Risk Factors; D012572:School Health Services; D012878:Skin Neoplasms / Q000209:etiology / Q000517:prevention & control; D013471:Sunburn / Q000150:complications / Q000453:epidemiology / Q000517:prevention & control*; D013997:Time Factors; D014904:Western Australia / Q000453:epidemiology