Obesity Abstracts

Background: The location of takeaway food shops is becoming increasingly studied in the UK with growing concerns around diet and obesity. UK planning policies to limit takeaways have been poorly thought out compared to other countries. There are no standardised measures used to measure the food environment around homes, schools, work or any other facilities. This study aims to examine the differences in using different methods to evaluate the food environment particularly around secondary schools in the Avon region in the UK.

Methods: Geographical Information System was used to locate all schools and takeaways in the region and to measure the density and proximity scores, applying both road network and straight-line methods. In addition, the Hansen Index was used to measure the accessibility score of each school to all takeaways in the region (not just the nearest). All of the statistical analysis tests were carried out using Stata software.

Results: More than half of the schools had no takeaway outlets within 200, 400, and 600 metres when the road network buffer was used. Wilcoxon signed ranked test results showed statistical significant differences in the density and proximity of takeaways between both circular and road network methods. The results also showed that there were fair and moderate agreement between straight-line and road network densities within 800 and 1000 metres, respectively. Also, the agreement between both methods to measure the proximity was fair to moderate. In addition, correlation test showed that the accessibility score was not dependent on the distance between the school and the nearest takeaway outlet using either the straight-line or the road network distances.

Conclusions: We recommend the use of 800 and 1000 road network metres and based on our findings the agreement between both methods to measure the density and proximity was not strong. A consistent approach to the methods used to measure the density, proximity or accessibility of food outlets, particularly around schools, is needed. This may help to enable promising policies to be implemented by governmental organisations and all related stakeholders and to effectively evaluate the impact of limiting the number of takeaway outlets around schools.