The relationships between food environments and dietary intake have been assessed via a range of methodologically diverse measures of spatial exposure to food outlets, resulting in a largely inconclusive body of evidence, limiting informed policy intervention. This systematic review aims to evaluate the influence of methodological choice on study outcomes by examining the within-study effect of availability (e.g., counts) versus accessibility (e.g., proximity) spatial exposure measures on associations with diet. (PROSPERO registration: CRD42018085250). PubMed, Web of Science, Scopus and ScienceDirect databases were searched for empirical studies from 1980 to 2017, in the English language, involving adults and reporting on the statistical association between a dietary outcome and spatial exposure measures of both availability and accessibility. Studies were appraised using an eight-point quality criteria with a narrative synthesis of results. A total of 205 associations and 44 relationships (i.e., multiple measures of spatial exposure relating to a particular food outlet type and dietary outcome) were extracted from 14 eligible articles. Comparative measures were dominated by counts (availability) and proximity (accessibility). Few studies compared more complex measures and all counts were derived from place-based measures of exposure. Sixteen of the 44 relationships had a significant effect involving an availability measure whilst only 8 had a significant effect from an accessibility measure. The largest effect sizes in relationships were mostly for availability measures. After stratification by scale, availability measure had the greatest effect size in 139 of the 176 pairwise comparisons. Of the 33% (68/205) of associations that reached significance, 53/68 (78%) were from availability measures. There was no relationship between study quality and reported study outcomes. The limited evidence suggests that availability measures may produce significant and greater effect sizes than accessibility measures. However, both availability and accessibility measures may be important concepts of spatial exposure depending on the food outlet type and dietary outcome examined. More studies reporting on multi-method effects are required to differentiate findings by the type of spatial exposure assessment and build an evidence base regarding the appropriateness and robustness of measures under different circumstances.

Objective: To examine the associations of changes in the local food environment, individual behaviours and perceptions with changes in dietary intake, following relocation from an established neighbourhood to a new residential development.Design: Spatial food environment exposure measures were generated relative to each participant’s home address using the locations of food outlets at baseline (before moving house) and follow-up (1–2 years after relocation). Self-reported data on socio-demographics, self-selection, usual dietary intake, individual behaviours and perceptions of the local food environment were sourced from the RESIDential Environments (RESIDE) Project. Changes in spatial exposure measures, individual behaviours and perceptions with changes in dietary outcomes were examined using mixed linear models.Setting: Perth, Western Australia, 2003–2007.Participants: Adults (n1200) from the RESIDE Project.Results: Moving to a new residential development with more convenience stores and café restaurants around the home was significantly associated with an increase in unhealthy food intake (β= 0·049, 95 % CI 0·010, 0·089;β= 0·020, 95 % CI 0·007, 0·033) and was partially mediated by individual behaviours and perceptions. A greater percentage of healthy food outlets around the home following relocation was significantly associated with an increase in healthy food (β= 0·003, 95 % CI 0·001, 0·005) and fruit/vegetable intake (β= 0·002, 95 % CI 0·001, 0·004).Conclusions: Policy and planning may influence dietary intakes by restricting the number of convenience stores and other unhealthy food outlets and increasing the relative percentage of healthy food outlets.

Issue addressed: Locating fast‐food outlets near schools is a potential public health risk to schoolchildren, given the easy access and repeated exposure to energy‐dense, nutrient‐poor foods they provide. Fast‐food outlet availability near schools has not been previously investigated in Perth, Western Australia. This study aimed to quantify fast‐food outlet availability near Perth schools and determine whether differences in area‐level disadvantage and school type exist.Methods: Fast‐food outlet locations were sourced from Perth Local Governments in 2018/2019. All Perth Primary (n = 454), Secondary (n = 107) and K‐12 (n = 94) schools were assigned an area‐level disadvantage decile ranking based on the Australian Bureau of Statistics Socio‐Economic Index for Areas (SEIFA). Regression models assessed whether fast‐food outlet availability within 400 m, 800 m and 1 km of schools differed by school type (ie, Primary/Secondary/K‐12) or SEIFA.Results: Secondary schools were significantly more likely than Primary and K‐12 schools to have a higher presence and density of fast‐food outlets and the “Top 4” fast‐food outlet chains (McDonalds, Hungry Jacks, KFC and Red Rooster) nearby. Schools located in low socio‐economic status (SES) areas had a significantly higher density of fast‐food outlets within 400 m, and “Top 4” fast‐food outlet chains within 400 m and 1 km, than schools located in high SES area.Conclusions: Perth schools are surrounded by fast‐food outlets with densities significantly higher around secondary schools and schools located in lower SES areas.So what?: Policies and regulations aimed at reducing fast‐food outlets near schools is an essential strategy to improve dietary intakes and reduce obesity in schoolchildren.

Large, longitudinal surveys often lack consistent dietary data, limiting the use of existing tools and methods that are available to measure diet quality. This study describes a method that was used to develop a simple index for ranking individuals according to their diet quality in a longitudinal study. The RESIDential Environments (RESIDE) project (2004–2011) collected dietary data in varying detail, across four time points. The most detailed dietary data were collected using a 24-item questionnaire at the final time point (n = 555; age ≥ 25 years). At preceding time points, sub-sets of the 24 items were collected. A RESIDE dietary guideline index (RDGI) that was based on the 24-items was developed to assess diet quality in relation to the Australian Dietary Guidelines. The RDGI scores were regressed on the longitudinal sub-sets of six and nine questionnaire items at T4, from which two simple index scores (S-RDGI1 and S-RDGI2) were predicted. The S-RDGI1 and S-RDGI2 showed reasonable agreement with the RDGI (Spearman’s rho = 0.78 and 0.84; gross misclassification = 1.8%; correct classification = 64.9% and 69.7%; and, Cohen’s weighted kappa = 0.58 and 0.64, respectively). For all of the indices, higher diet quality was associated with being female, undertaking moderate to high amounts of physical activity, not smoking, and self-reported health. The S-RDGI1 and S-RDGI2 explained 62% and 73% of the variation in RDGI scores, demonstrating that a large proportion of the variability in diet quality scores can be captured using a relatively small sub-set of questionnaire items. The methods described in this study can be applied elsewhere, in situations where limited dietary data are available, to generate a sample-specific score for ranking individuals according to diet quality.