Does the choice of neighbourhood supermarket access measure influence associations with individual-level fruit and vegetable consumption? A case study from Glasgow

Abstract

BackgroundPrevious studies have provided mixed evidence with regards to associations between food store access and dietary outcomes. This study examines the most commonly applied measures of locational access to assess whether associations between supermarket access and fruit and vegetable consumption are affected by the choice of access measure and scale.MethodSupermarket location data from Glasgow, UK (n = 119), and fruit and vegetable intake data from the ‘Health and Well-Being’ Survey (n = 1041) were used to compare various measures of locational access. These exposure variables included proximity estimates (with different points-of-origin used to vary levels of aggregation) and density measures using three approaches (Euclidean and road network buffers and Kernel density estimation) at distances ranging from 0.4 km to 5 km. Further analysis was conducted to assess the impact of using smaller buffer sizes for individuals who did not own a car. Associations between these multiple access measures and fruit and vegetable consumption were estimated using linear regression models.ResultsLevels of spatial aggregation did not impact on the proximity estimates. Counts of supermarkets within Euclidean buffers were associated with fruit and vegetable consumption at 1 km, 2 km and 3 km, and for our road network buffers at 2 km, 3 km, and 4 km. Kernel density estimates provided the strongest associations and were significant at a distance of 2 km, 3 km, 4 km and 5 km. Presence of a supermarket within 0.4 km of road network distance from where people lived was positively associated with fruit consumption amongst those without a car (coef. 0.657; s.e. 0.247; p0.008).ConclusionsThe associations between locational access to supermarkets and individual-level dietary behaviour are sensitive to the method by which the food environment variable is captured. Care needs to be taken to ensure robust and conceptually appropriate measures of access are used and these should be grounded in a clear a priori reasoning.

Exploring the Relation of Spatial Access to Fast Food Outlets With Body Weight: A Mediation Analysis

“…The implications of using different concepts (availability, proximity, spatial access) have previously been outlined (Burgoine, Alvanides, & Lake, 2013;Caspi, Sorensen, Subramanian, & Kawachi, 2012;Charreire et al, 2010;Roda et al, 2016;Thornton, Pearce, Macdonald, Lamb, & Ellaway, 2012). The usefulness of each of these concepts may depend on the characteristics of the areas under study.…”

Concerning Limitations of Food-Environment Research: A Narrative Review and Commentary Framed around Obesity and Diet-Related Diseases in Youth

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“…§ However, linear distances may be poor measures of actual exposure or accessibility. [101][102][103][104] For instance, straight lines ignore possible travel routes and barriers to transit like train tracks, rivers, and divided highways.…”

Spatial and Semantic Validation of Secondary Food Source Data

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“…The food environment includes places where food can be acquired, such as supermarkets, bakeries and restaurants [1]. This physical food environment influences the types and amounts of food available and the opportunity for choosing a healthful diet [2,3]. Insights into food environments and nutritional behavior can facilitate human wellbeing and improve nutritional benefits [4].…”