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Neighbourhood effects: Spatial inequalities in tooth decay

Neighbourhood effects: Spatial inequalities in tooth decay
Tom Broomhead


School of Clinical Dentistry, The University of Sheffield, Sheffield, South Yorkshire S10 2TN, UNITED KINGDOM.


Objectives: Little theoretical work has been conducted on the topic of neighbourhood effects on health outcomes, let alone within dentistry. Previous work has often quantified and described outcomes without proper investigation of potential causal mechanisms and pathways. Therefore, the aim of this exploratory research was to investigate features of neighbourhood environments that may influence tooth decay in adults.

Methods: Relevant literature was mapped onto a neighbourhood based theoretical framework to create numerous pathways by which neighbourhoods influence decay. Spatial microsimulation was used to combine data from the Adult Dental Health Survey (2009) with Census data to create a synthetic dataset of individuals at the small area level for the city of Sheffield (UK), including associated socio-economic, demographic and dental characteristics. This data formed the basis of the agent-based models which were used to test the theoretical pathways in two contrasting study areas in Sheffield, as well as a hypothetical scenario involving an extra shop being added to each location.

Results: The trends of the agent-based models indicated that the same pathway (the interaction between shops, diet and sugar intake) had the largest impact in both study areas, leading to statistically significant increases in decay in both cases (p < 0.05). The results of the hypothetical simulation involving an extra shop revealed a statistically significant decrease in decay in the more affluent study area (p < 0.05), while decay scores remained similar in the less affluent study area.

Conclusions: The findings suggest the interactions between shops, diet and sugar intake may be the most important neighbourhood based mechanisms for tooth decay, regardless of socio-economic status. However, additional simulations pointed to more opportunities to reduce decay in the more affluent study area through the local food environment. The implications of these findings are discussed in light of previous research and future work.