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Adolescents' use of purpose built shade in secondary schools: cluster randomised controlled trial
Suzanne J Dobbinson1, Vanessa White, Melanie A Wakefield
1Centre for Behavioural Research in Cancer, Cancer Council Victoria, 1 Rathdowne Street, Carlton, Vic 3053, Australia. Suzanne.Dobbinson@cancervic.org.au
Objective:
To examine whether students use or avoid newly shaded areas created by shade sails installed at schools.
Design:
Cluster randomised controlled trial with secondary schools as the unit of randomisation.
Setting:
51 secondary schools with limited available shade, in Australia, assessed over two spring and summer terms.
Participants:
Students outside at lunch times.
Intervention:
Purpose built shade sails were installed in winter 2005 at full sun study sites to increase available shade for students in the school grounds.
Main Outcome Measure:
Mean number of students using the primary study sites during weekly observations at lunch time.
Results:
Over the study period the mean change in students using the primary study site from pre-test to post-test was 2.63 (95% confidence interval 0.87 to 4.39) students in intervention schools and -0.03 (-1.16 to 1.09) students in control schools. The difference in mean change between groups was 2.67 (0.65 to 4.68) students (P=0.011).
Conclusions:
Students used rather than avoided newly shaded areas provided by purpose built shade sails at secondary schools in this trial, suggesting a practical means of reducing adolescents' exposure to ultraviolet radiation.
Trial Registration:
Exempt.
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