Abstract
Purpose: :
To evaluate a novel incentive-based outdoor-physical activity intervention to increase time spent outdoors and physical activity among children aged 6 to 12 years in a 1-year randomized controlled trial, and determine its value in protecting against myopia and improving overall fitness.
Methods: :
285 children were randomized to either the intervention (n= 147) or control arm (n= 138) in the one-year Family Incentive Trial (FIT). Outdoor time from the diary and portable light meter over a 1 week period was also compared in a subset of 117 children. The intervention comprised of structured weekend outdoor activities in parks and incentives for children to increase their daily steps as measured via pedometers. Outdoor time from the WHO questionnaire was measured.
Results: :
There were154 boys and 131 girls, 86% of participants were Chinese, 4.2% Malays, 6% Indians, and 3.9% of other races, and 58.5% were myopic at baseline. The intraclass correlation coefficients were 0.21 and 0.28 of outdoor time from the diary and light meter (1000 Lux cut-off) during the school term and holidays, respectively. On average, 77.8% of the children in the intervention group achieved the pedometer step goal of 8,000 steps for more than 15 days per month and attended 1.5 parks per month. The total number of hours spent per week from the questionnaires in the intervention group was 14.9 versus 12.1 hours per week in the control group (p=0.011), with most of the increase occurring on weekends (2.9 versus 2.4 hours per weekend day; p= 0.009).
Conclusions: :
Outdoor time increased by more than 3 hours per week for children randomized to the novel incentive-based outdoor-physical activity program designed to reduce refractive shifts towards myopia. The agreement between the light meter and 1 week diary was poor to fair, time outdoors and light intensity could capture different aspects of risk in future myopia studies. This trial suggest it may be possible to increase outdoor activities in children to delay shifts towards myopic refractions.
Clinical Trial: :
http://www.clinicaltrials.gov NCT01388205
Keywords: myopia • refractive error development • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials