Using GPS and activity tracking to reveal the influence of adolescents' food environment exposure on junk food purchasing

The impact of smartphone app-based interventions on adolescents' dietary intake: a systematic review and evaluation of equity factor reporting in intervention studies

CONTEXT

Adolescence is a critical stage for improving nutrition. The popularity of smartphones makes them an ideal platform for administering interventions to adolescents. A systematic review has yet to assess the impact of smartphone app-based interventions exclusively on adolescents' dietary intake. Furthermore, despite the impact of equity factors on dietary intake and the claim for mobile health of increased accessibility, there is minimal research on the reporting of equity factors in the evaluation of smartphone app-based nutrition-intervention research.

OBJECTIVES

This systematic review examines the effectiveness of smartphone app-based interventions on adolescents' dietary intake and the frequency with which equity factors and statistical analyses specific to equity factors are reported in these intervention studies.

DATA SOURCES

Databases (ie, Scopus, CINAHL, EMBASE, MEDLINE, PsycINFO, ERIC, and Cochrane Central Register for Randomized Control Trials) were searched for studies published from January 2008 to October 2022. Smartphone app-based intervention studies that were nutrition focused, evaluated at least 1 dietary intake variable, and included participants with a mean age between 10 and 19 years were included. All geographic locations were included.

DATA EXTRACTION AND ANALYSIS

Study characteristics, intervention results, and reported equity factors were extracted. Because of the heterogeneity of dietary outcomes, findings were reported as a narrative synthesis.

CONCLUSION

In total, 3087 studies were retrieved, 14 of which met the inclusion criteria. Eleven studies reported a statistically significant improvement in at least 1 dietary outcome because of the intervention. Reporting of at least 1 equity factor across articles' Introduction, Methods, Results, and Discussion sections was minimal (n = 5), and statistical analyses specific to equity factors were rare, occurring in only 4 of the 14 included studies. Future interventions should include a measurement of intervention adherence and report the impact of equity factors on the effectiveness and applicability of interventions for equity-deserving groups.

Food environment research in Canada: a rapid review of methodologies and measures deployed between 2010 and 2021

Numerous research methodologies have been used to examine food environments. Existing reviews synthesizing food environment measures have examined a limited number of domains or settings and none have specifically targeted Canada. This rapid review aimed to 1) map research methodologies and measures that have been used to assess food environments; 2) examine what food environment dimensions and equity related-factors have been assessed; and 3) identify research gaps and priorities to guide future research. A systematic search of primary articles evaluating the Canadian food environment in a real-world setting was conducted. Publications in English or French published in peer-reviewed journals between January 1 2010 and June 17 2021 and indexed in Web of Science, CAB Abstracts and Ovid MEDLINE were considered. The search strategy adapted an internationally-adopted food environment monitoring framework covering 7 domains (Food Marketing; Labelling; Prices; Provision; Composition; Retail; and Trade and Investment). The final sample included 220 articles. Overall, Trade and Investment (1%, n = 2), Labelling (7%, n = 15) and, to a lesser extent, Prices (14%, n = 30) were the least studied domains in Canada. Among Provision articles, healthcare (2%, n = 1) settings were underrepresented compared to school (67%, n = 28) and recreation and sport (24%, n = 10) settings, as was the food service industry (14%, n = 6) compared to grocery stores (86%, n = 36) in the Composition domain. The study identified a vast selection of measures employed in Canada overall and within single domains. Equity-related factors were only examined in half of articles (n = 108), mostly related to Retail (n = 81). A number of gaps remain that prevent a holistic and systems-level analysis of food environments in Canada. As Canada continues to implement policies to improve the quality of food environments in order to improve dietary patterns, targeted research to address identified gaps and harmonize methods across studies will help evaluate policy impact over time.

Global positioning system-based food environment exposures, diet-related, and cardiometabolic health outcomes: a systematic review and research agenda

BACKGROUND

Geographic access to food may affect dietary choices and health outcomes, but the strength and direction of associations may depend on the operationalization of exposure measures. We aimed to systematically review the literature on up-to-date evidence on the association between food environment exposures based on Global Positioning System (GPS) and diet-related and cardiometabolic health outcomes.

METHODS

The databases PubMed, Embase.com, APA PsycInfo (via Ebsco), Cinahl (via Ebsco), the Web of Science Core Collection, Scopus, and the International Bibliography of the Social Sciences (via ProQuest) were searched from inception to October 31, 2022. We included studies that measured the activity space through GPS tracking data to identify exposure to food outlets and assessed associations with either diet-related or cardiometabolic health outcomes. Quality assessment was evaluated using the criteria from a modified version of the Newcastle-Ottawa Scale (NOS) for cross-sectional studies. We additionally used four items from a quality assessment tool to specifically assess the quality of GPS measurements.

RESULTS

Of 2949 studies retrieved, 14 studies fulfilled our inclusion criteria. They were heterogeneous and represent inconsistent evidence. Yet, three studies found associations between food outlets and food purchases, for example, more exposure to junk food outlets was associated with higher odds of junk food purchases. Two studies found associations between greater exposure to fast food outlets and higher fast food consumption and out of three studies that investigated food environment in relation to metabolic outcomes, two studies found that higher exposure to an unhealthy food environment was associated with higher odds of being overweight.

CONCLUSIONS

The current and limited evidence base does not provide strong evidence for consistent associations of GPS-based exposures of the food environment with diet-related and cardiometabolic health outcomes.

Sedentary Activities and Food Intake among Children and Adolescents in the Zhejiang Province of China: A Cross-Sectional Study

BACKGROUND

Sedentary behavior may affect the types of food consumed in children and adolescents' daily diets. Previous published studies are limited to local surveys. This study aimed to explore the relationship between sedentary behavior and food intake among children and adolescents.

METHODS

A stratified sampling technique was employed in the present cross-sectional study. Demographic characteristics, sedentary behavior, transportation modes, and food intake were investigated.

RESULTS

We found that children and adolescents who watched movies or TV programs online or on their smartphones on weekends and who chatted online on weekends, including on QQ (an instant messaging software service) and WeChat (an instant messaging software service), increased their intake of instant noodles and fried pasta (Spearman's rho = 0.468, 0.575, 0.465, and 0.323; p < 0.05). Children and adolescents who chatted online on weekends, including on QQ and WeChat, increased their intake of tofu skin (Spearman's rho = 0.461; p < 0.05), and those who browsed online on weekdays increased their intake of whole-fat liquid milk (Spearman's rho = 0.455; p < 0.05). Children and adolescents who browsed and chatted online on weekends, including on QQ and WeChat, and who played computer or smartphone games, increased their intake of fried potato chips (French fries or other fried snacks) (Spearman's rho = 0.568, 0.270, and 0.412; p < 0.05). With respect to modes of transportation used to travel to and from school, children and adolescents who took buses and subways increased their intake of rice, instant noodles, sweet potatoes, soybean milk, tofu skin, processed meat products (sausage, ham sausage, or lunch meat), fish, shrimp, vegetables, nuts, and sweet cookies (buns, cakes, Dim sum, and moon cakes) (Spearman's rho = 0.394, 0.536, 0.630, 0.408, 0.485, 0.441,0.410, 0.424, 0.444, 0.541, and 0.366; p < 0.05).

CONCLUSIONS

Sedentary behavior affects the types of food consumed in children and adolescents' daily diets. Children and adolescents who browsed online on weekdays increased their intake of whole-fat liquid milk, but also increased their intake of foods with high fat, high salt, and low nutrient density. Children and adolescents taking buses and subways increased their intake of low-nutrition quality products. Public awareness efforts should focus on reducing the consumption of low-nutrition quality products and nutritional education.

The campus food environment and postsecondary student diet: a systematic review

Objective: Examine the impact of the campus food environment on postsecondary students' dietary behaviors (e.g., dietary intake) and food purchasing. Participants: Students currently attending a postsecondary institution, all ages and geographic locations included. Methods: A systematic search from January 2000-October 2022 was conducted in six databases using postsecondary education, food environment, and diet related keywords. Results: In total, 25 quantitative and 10 qualitative studies were extracted. All quantitative studies that conducted statistical analyses (n = 15) reported a statistically significant relationship between the campus food environment and dietary intake, including both positive and negative effects. All qualitative studies (n = 10) discussed students' experience of the campus food environment influencing their diet. Conclusions: This review found moderate evidence that the campus food environment has an impact on postsecondary students' dietary behaviors. A campus environment that has healthy foods accessible, affordable, and acceptable for postsecondary students may have a beneficial impact on students' dietary intake.

Influences of the community and consumer nutrition environment on the food purchases and dietary behaviors of adolescents: A systematic review

Adolescence is a period of increased autonomy over decision-making, including food choices, and increased exposure to influences outside the home, including the food environment. This review aims to synthesize the evidence for the influence of community nutrition environments, spatial access to food outlets, and consumer nutrition environments, environments inside food outlets, on adolescent food purchasing and dietary behaviors in high-income countries. Six databases were searched for articles published before January 2023. Results were synthesized using a vote-counting technique and effect direction plots that record the direction of the effect in relation to the anticipated relationship with health. Thirty-four observational and two intervention studies met the inclusion criteria. In the 13 studies assessing adolescent exposure to healthy community nutrition environments, results did not show clear associations with dietary and purchasing outcomes. Thirty studies assessed adolescents' exposure to unhealthy community nutrition environments with the majority (n = 17/30, 57%) reporting results showing that greater exposure to food outlets classified as unhealthy was associated with less healthy food purchases and dietary intakes. Inconsistent results were observed across the seven studies investigating associations with the consumer environment. Further research in these areas, including more high-quality intervention studies, may help to develop policy strategies to improve adolescents' dietary behaviors.

Analyzing differences between spatial exposure estimation methods: A case study of outdoor food and beverage advertising in London, Canada

Exposure assessment in the context of mobility-oriented health research often is challenged by the type of spatial measurement technique used to estimate exposures to environmental features. The purpose of this study is to compare smartphone global positioning system (GPS), shortest network path mobility, and buffer-based approaches in estimating exposure to outdoor food and beverage advertising among a sample of 154 teenagers involved in the SmartAPPetite study during 2018 in London, Ontario, Canada. Participants were asked to report their home postal code, age, gender identity, ethnicity, and number of purchases they had made at a retail food outlet in the past month. During the same time period, a mobile phone application was used to log their mobility and specifically record when a participant was in close proximity to outdoor advertising. The results of negative binomial regression modelling reveal significant differences in estimates of advertising exposure, and the relationship to self-reported purchasing. Spatial exposure estimation methods showed differences across regression models, with the buffer and observed GPS approaches delivering the best fitting models, depending on the type of retail food outlet. There is a clear need for more robust research of spatial exposure measurement techniques in the context of mobility and food (information) environment research.

Survey-derived activity space-based exposures to fast food outlets and their cross-sectional associations with use of fast food outlets, diet quality and BMI

There is a need for conceptual and methodological innovation in food environment-health research. We compared different operationalizations of survey-derived activity space exposures to fast food outlets (FFOs) in associations with use of FFO, diet quality and body mass index (BMI). FFO exposure was determined for home, work and a maximum of sixteen other locations reported by 1728 Dutch adults. Considerable differences in count of FFO between locations were found. Adjusted linear regression analyses resulted in small, unexpected associations with use of FFO, diet quality and BMI, whereby the strength of associations differed between exposure measures. Using home and work areas may be a cost-efficient compromise to capture large parts of the exposure to FFOs.

Adolescents’ School Travel and Unhealthy Snacking: Associations with School Transport Modes, Neighbourhood Deprivation, and Body Weight

Active transport to and/or from school (ATS), alone or combined with motorised transport, provides an opportunity to increase adolescents’ physical activity levels to prevent obesity. However, travel through and exposure to an unhealthy food environment en route to school may have unintended consequences, specifically unhealthy snacking. This study examined the association between adolescents’ unhealthy snack food/soft drink purchases/consumption during the journey to and from school and their school transport modes, neighbourhood deprivation, and body weight. Adolescents (n = 660, age: 15.3 ± 1.3 years, 51.7% female) from 11 schools in the Otago region, New Zealand, completed an online survey and anthropometry. Data were analysed using χ2 test and logistic regression. Overall, 36.7% of adolescents purchased/consumed unhealthy snack foods and 25.9% purchased/consumed soft drinks at least once during their weekly school trips. ATS and mixed transport users reported more frequent unhealthy snack food/soft drinks purchases/consumption on the way to school than motorised transport users. Neighbourhood deprivation, but not body weight, was positively associated with unhealthy snack food/soft drink purchases/consumption during the school journey. Our findings highlight the importance of considering not only travel mode shift but also the obesogenic environment and unhealthy food/drinks purchases/consumption during adolescents’ school journeys, particularly in lower socio-economic areas, to prevent obesity.

Children's Community Nutrition Environment, Food and Drink Purchases and Consumption on Journeys between Home and School: A Wearable Camera Study

Children's community nutrition environments are an important contributor to childhood obesity rates worldwide. This study aimed to measure the type of food outlets on children's journeys to or from school, children's food purchasing and consumption, and to determine differences by ethnicity and socioeconomic status. In this New Zealand study, we analysed photographic images of the journey to or from school from a sample of 147 children aged 11-13 years who wore an Autographer camera which recorded images every 7 s. A total of 444 journeys to or from school were included in the analysis. Camera images captured food outlets in 48% of journeys that had a component of active travel and 20% of journeys by vehicle. Children who used active travel modes had greater odds of exposure to unhealthy food outlets than children who used motorised modes; odds ratio 4.2 (95% CI 1.2-14.4). There were 82 instances of food purchases recorded, 84.1% of which were for discretionary foods. Of the 73 food and drink consumption occasions, 94.5% were for discretionary food or drink. Children on their journeys to or from school are frequently exposed to unhealthy food outlets. Policy interventions are recommended to limit the availability of unhealthy food outlets on school routes.

Neighbourhood food typologies, fast food outlet visitation and snack food purchasing among adolescents in Melbourne, Australia

OBJECTIVE

Despite the increased attention on neighbourhood food environments and dietary behaviours, studies focusing on adolescents are limited. This study aims to characterise typologies of food environments surrounding adolescents and their associations with fast food outlet visitation and snack food purchasing to/from school.

DESIGN

The number of food outlets (supermarket; green grocers; butcher/seafood/deli; bakeries; convenience stores; fast food/takeaways; café and restaurants) within a 1 km buffer from home was determined using a Geographic Information System. Adolescents' self-reported frequency of fast food outlet visitation and snack food purchasing to/from school. Latent Profile Analysis was conducted to identify typologies of the food environment. Cross-sectional multilevel logistic regression analyses were conducted to examine the relationships between food typologies, fast food outlet visitations and snack food purchasing to/from school.

SETTING

Melbourne, Australia.

PARTICIPANTS

Totally, 410 adolescents (mean age= 15·5 (sd = 1·5) years).

RESULTS

Four distinct typologies of food outlets were identified: (1) limited variety/low number; (2) some variety/low number; (3) high variety/medium number and (4) high variety/high number. Adolescents living in Typologies 1 and 2 had three times higher odds of visiting fast food outlets ≥1 per week (Typology 1: OR = 3·71, 95 % CI 1·23, 11·19; Typology 2: OR = 3·65, 95 % CI 1·21, 10·99) than those living in Typology 4. No evidence of association was found between typologies of the food environments and snack food purchasing behaviour to/from school among adolescents.

CONCLUSION

Local government could emphasise an overall balance of food outlets when designing neighbourhoods to reduce propensity for fast food outlet visitation among adolescents.

Linking the Flint Food Store Survey: Is Objective or Perceived Access to Healthy Foods Associated with Glycemic Control in Patients with Type 2 Diabetes?

Type 2 diabetes mellitus (DM-2) remains a significant public health concern, particularly in low-income neighborhoods where healthy foods may be scarcer. Despite the well-known relationship between diet and diabetes, little evidence exists on the connections among the objectively measured community and consumer food environment, perception of food access, and diabetes management or outcomes. This cross-sectional, ecological study represents the first example of combining a GIS-based, objectively measured food store audit considering quality, variety, and price of foods in stores with a clinical survey of patients with DM-2 (n = 126). In this way, we offer evidence on the relationship between healthy food access-measured more robustly than proximity to or density of certain store types-and diabetes management knowledge, medication adherence, and glycemic control. Better glycemic control was not correlated with better overall food store score, meaning that people in neighborhoods with better access to healthy foods are not necessarily more likely to manage their diabetes. While perceived healthy food access was not correlated with glycemic control, it was strongly correlated with objective healthy food access at shorter distances from home. These results have great importance both for clinical understanding of the persistence of poor diabetes management outcomes and for the understanding of the influence of the food environment on health behaviors.

Exploring factors affecting individual GPS-based activity space and how researcher-defined food environments represent activity space, exposure and use of food outlets

Background

Obesity remains one of the most challenging public health issues of our modern time. Despite the face validity of claims for influence, studies on the causes of obesity have reported the influence of the food environment to be inconsistent. This inconsistency has been attributed to the variability of measures used by researchers to represent the food environments—Researcher-Defined Food Environments (RDFE) like circular, street-network buffers, and others. This study (i.) determined an individual’s Activity Space (AS) (ii.) explored the accuracy of the RDFE in representing the AS, (iii.) investigated the accuracy of the RDFE in representing actual exposure, and (iv.) explored whether exposure to food outlet reflects the use of food outlets.

Methods

Data were collected between June and December 2018. A total of 65 participants collected Global Positioning System (GPS) data, kept receipt of all their food purchases, completed a questionnaire about their personal information and had their weight and height measured. A buffer was created around the GPS points and merged to form an AS (GPS-based AS).

Results

Statistical and geospatial analyses found that the AS size of participants working away from home was positively related to the Euclidean distance from home to workplace; the orientation (shape) of AS was also influenced by the direction of workplace from home and individual characteristics were not predictive of the size of AS. Consistent with some previous studies, all types and sizes of RDFE variably misrepresented individual exposure in the food environments. Importantly, the accuracy of the RDFE was significantly improved by including both the home and workplace domains. The study also found no correlation between exposure and use of food outlets.

Conclusions

Home and workplace are key activity nodes in modelling AS or food environments and the relationship between exposure and use is more complex than is currently suggested in both empirical and policy literature.

Seeing the food swamp for the weeds: Moving beyond food retail mix in evaluating young people's food environments

Nutritional health of children and youth is an increasing cause for concern in Canada. Through food and beverage messaging in multiple environments, young people develop eating behaviours with ramifications throughout their life course. Unhealthy food retailers near schools, recreation facilities, and childcare centres-key activity settings for healthy eating promotion-present repeated, compounding exposures to commercial geomarketing. Geomarketing impacts nutritional health by promoting highly processed, calorie-dense, and nutrient-poor foods and beverages across urban landscapes. While food retail mix (as a ratio of healthy to unhealthy food retailers) can be used to assess food environments at multiple scales, such measures may misrepresent young people's unique experience of these geographic phenomena. Moving beyond uniform conceptualization of food environments, new research methods and tools are needed for children and youth. We investigated young people's food environments in the major Canadian cities of Calgary and Edmonton. Using government-initiated nutrition guidelines, we categorized 55.8% of all food retailers in Calgary, and 59.9% in Edmonton as 'unhealthy'. A Bernoulli trial at the 0.05 alpha level indicated few differences in prevalence proximal to activity settings versus elsewhere in both cities, demonstrating the limited applicability of food retail mix for characterizing young people's food environments. To model unhealthy food retailers geomarketing to children and youth, we considered their proximity to multiple activity settings, using overlapping radial buffers at the 250 m, 500 m, 1000 m, and 1500 m scales. Examining young people's food environments relative to the spaces where they learn and play, we determined that as many as 895 out of 2663 unhealthy food retailers fell within 1500 m of 21+ activity settings. By conceptualizing, measuring, and problematizing these "super-proximal" unhealthy food retailers, urban planners and public health researchers can use these techniques to pinpoint unhealthy food retailers, or "weeds in the food swamp," as a critical site for healthy eating promotion in municipalities.

Combining Global Positioning System (GPS) with saliva collection among sexual minority adults: A feasibility study

BACKGROUND

This is the first study, of which we are aware, to evaluate the feasibility and accessibility of simultaneous use of Global Positioning System (GPS) and saliva collection for biomarker assessment as an objective measure of stress physiology among sexual minority (lesbian, gay, bisexual, queer, and other non-heterosexual identities) individuals. The principal motivation for pairing GPS and saliva collection was to investigate how characteristics of the built and social environments along with participants' daily activity paths affect stress. This can contribute to a better understanding of health and health behaviors in the sexual minority community.

METHODS

A convenience sample of enrolled participants (N = 124) from Houston, Texas was asked to complete questionnaires, carry with them a GPS unit daily, and collect and store 6 samples of saliva at specific times across the span of a day prior to a second visit around one week later.

RESULTS

Of 124 participants, 16 participants (12.90%) provided no useable GPS data and 98 (79.03%) provided at least 4 days of data. More than three-fourths (n = 98, 79.03%) also provided complete saliva samples.

CONCLUSIONS

Our results show that the simultaneous use of GPS and saliva collection to assess sexual minority individuals' activity paths and stress level is feasible.

Measuring neighborhood deprivation for childhood health and development - scale implications in rural and urban context

Neighborhood deprivation plays an important role in childhood health and development, but defining the appropriate neighborhood definition presents theoretical as well as practical challenges. Few studies have compared neighborhood definitions outside of highly urbanized settings. The purpose of the current study was to evaluate how various administrative and ego-centric neighborhood definitions may impact measured exposure to deprivation across the urban-rural continuum. We do so using the Family Life Project, a prospective longitudinal population-based sample of families living in North Carolina and Pennsylvania (USA), which also sets the stage for future investigations of neighborhood impacts on childhood health and development. To measure neighborhood deprivation, a standardized index of socioeconomic deprivation was calculated using data from the 2007-2011 American Community Survey. Families' residential addresses when children were 2 months of age (n=1036) were geocoded and overlaid onto a deprivation index layer created at the census block group level to construct multiple administrative and ego-centric neighborhood definitions. Friedman tests were used to compare distributions of neighborhood deprivation across these neighborhood definitions within urbanized areas, urban clusters, and rural areas. Results indicated differences in urbanized areas (Chisquare= 897.75, P<0.001) and urban clusters (Chi-square=687.83, P<0.001), but not in rural areas (Chi-square=13.52, P=0.332). Findings imply that in urban areas, choice of neighborhood definition impacts measured exposure to neighborhood deprivation. Although exposure to neighborhood deprivation appears to be less sensitive to neighborhood definition in rural areas, researchers should apply theoretical reasoning to choose appropriate definitions of children's neighborhood.

How Neighbourhood Food Environments and a Pay-as-You-Throw (PAYT) Waste Program Impact Household Food Waste Disposal in the City of Toronto

Household food waste has negative, and largely unnecessary, environmental, social and economic impacts. A better understanding of current household food waste disposal is needed to help develop and implement effective interventions to reduce food wasting. A four-season waste characterization study was undertaken with 200 single-family households across eight neighbourhoods in Toronto, Ontario, Canada. The City of Toronto provides residents with a pay-as-you-throw (PAYT) waste program that includes a choice of four garbage cart sizes (Small [S], Medium [M], Large [L], Extra Large [XL]), with increasing annual user fees ($18.00–$411.00 CAD), as well as a green cart (organic waste) and blue cart (recycling). On average, each household disposed 4.22 kg/week of total food waste, 69.90% of which was disposed in the green cart, and disposal increased significantly (p = 0.03) by garbage cart size to L but not XL garbage carts. Of this total, 61.78% consisted of avoidable food waste, annually valued at $630.00–$847.00 CAD/household. Toronto’s PAYT waste program has been effective at diverting food waste into the green cart but not at reducing its generation. Higher median incomes were positively correlated, while higher neighbourhood dwelling and population density were negatively correlated, with total and avoidable food waste disposal. Regression analyses explained 40–67% of the variance in total avoidable food waste disposal. Higher supermarket density and distance to healthier food outlets were associated with more, while dwelling density was related to less, total and avoidable food waste disposal. Distance to fast food restaurants and less healthy food outlet density were both negatively associated with avoidable food waste disposal in the garbage and green cart, respectively. Avoidable food waste reduction interventions could include increasing garbage cart fees, weight-based PAYT, or messaging to households on the monetary value of avoidable food waste, and working with food retailers to improve how households shop for their food.

Space-time analysis of unhealthy food advertising: New Zealand children's exposure and health policy options

Reducing children's exposure to unhealthy food advertising is an accepted strategy to end childhood obesity. This study aimed to (i) measure children's space-time exposures to unhealthy food advertising in public outdoor spaces, using GPS and wearable cameras; and (ii) test effectiveness of banning options. We compiled data (collected July 2014-June 2015) on 138 12-year-old children in Wellington, New Zealand, using wearable cameras and GPS devices worn over 4 days. In 2017-18, we linked 59 150 images taken in public outdoor spaces to GPS data. Of these, 1631 contained unhealthy food advertising exposures, defined as ≥50% of an advertisement observed in each image. We examined spatial patterns using kernel density mapping and graphed space-time trends. We interpolated a kriged exposure rate across Wellington to estimate exposure reductions for potential bans. Children were exposed to 7.4 (95% CI 7.0-7.8) unhealthy food advertisements/hour spent in outdoor public spaces. Exposures occurred in shopping centres, residential areas and sports facilities, commonly involving fast food, sugary drinks and ice cream. Peak exposure times were weekend afternoons/evenings and weekdays before/after school. In Wellington, we estimated that banning such advertising within 400 m of playgrounds would yield a 33% reduction in exposure, followed by in residential areas (27%), within 400 m of schools (25%), and 50% for a ban combining all above. This work documents the extent of children's exposure to unhealthy food advertising and the potential impact of bans. Given the ubiquity of advertising in public spaces, this New Zealand research offers innovative methods and findings likely relevant in other jurisdictions.

Association between time-weighted activity space-based exposures to fast food outlets and fast food consumption among young adults in urban Canada

BACKGROUND

Despite increased attention on retail food environments and fast food consumption, results from previous studies have been inconsistent. Variation in measurement of exposure to retail food environments and the context of the built environment are possible reasons for inconsistencies. The purpose of the current study is to examine the association between exposure to fast food environment and fast food consumption among young adults, and to explore possible associations between built environment and fast food consumption.

METHODS

We employed an observational, cross-sectional study design. Cross-sectional surveys were conducted in 2016 and 2017. In a sample of 591 young adults aged 16-30 years in five Canadian cities, we constructed and computed individual-level time-weighted number and ratio of fast food outlets in activity spaces derived from GPS trajectory data. Negative binomial regression models estimated the associations between exposure measures and frequency of fast food consumption (number of times consuming fast food meals in a seven-day period), controlling for built environment characterization and individual-level characteristics.

RESULTS

Significant positive associations were found between time-weighted number of fast food outlets and count of fast food meals consumed per week in models using a radius of 500 m (IRR = 1.078, 95% CI: 0.999, 1.163), 1 km (IRR = 1.135, 95% CI: 1.024, 1.259), or 1.5 km (IRR = 1.138, 95% CI: 1.004, 1.289) around GPS tracks, when generating activity spaces. However, time-weighted ratio of fast food outlets was only significantly associated with count of fast food meals consumed when a radius of 500 m is used (IRR = 1.478, 95% CI: 1.032, 2.123). The time-weighted Active Living Environment Index with Transit measure was significantly negatively related to count of fast food meals consumed across all models.

CONCLUSIONS

Our study demonstrated associations of time-weighted activity space-based exposure to fast food outlets and fast food consumption frequency in a sample of young adults in urban Canada, and provides evidence of the association between context of built environment and fast food consumption, furthering discussion on the utility of individual-level, activity space-based data and methods in food environment research. These results imply that both food retail composition and activity spaces in urban areas are important factors to consider when studying diets.

Looking Back and Moving Forward: The Evolution and Potential Opportunities for the Future of Alcohol Outlet Density Measurement

The literature consistently finds that areas with greater density of alcohol outlets (places that sell alcohol) tend to have higher levels of public health harms. However, conflicting findings arise when researchers drill down to identify the type(s) of alcohol outlets with the strongest associations with harms and the mechanisms that explain these associations. These disagreements could be a result of the outdated methods commonly used to quantify the alcohol environment: counts of the number of outlets in an area. This manuscript reviews the events and ideas that shaped the literature on the physical alcohol environment. It then defines the three main methods used to measure alcohol outlet density, conducts an exploratory factor analysis to explore the constructs underlying each method, and presents a novel conceptual framework that summarizes the three methods, their respective underlying constructs, and the setting(s) in which each may be most appropriate. The framework proposes that counts of alcohol outlets measure availability, proximity to the nearest outlet measures accessibility, and spatial access measures measure access, which comprises both availability and accessibility. We argue that researchers should consider using proximity and spatial access measures when possible and outline how doing so may present opportunities to advance theory and the design and implementation of alcohol outlet zoning regulations. Finally, this manuscript draws on research from other areas of the built environment to suggest opportunities to use novel methods to overcome common hurdles (e.g., separating subtypes of outlets, ecologic designs) and a new challenge on the horizon: home delivery.

A Smartphone App Combining Global Positioning System Data and Ecological Momentary Assessment to Track Individual Food Environment Exposure, Food Purchases, and Food Consumption: Protocol for the Observational FoodTrack Study

Background

Our understanding of how food choices are affected by exposure to the food environment is limited, and there are important gaps in the literature. Recently developed smartphone-based technologies, including global positioning systems and ecological momentary assessment, enable these gaps to be filled.

Objective

We present the FoodTrack study design and methods, as well as participants’ compliance with the study protocol and their experiences with the app. We propose future analyses of the data to examine individual food environmental exposure taking into account the accessible food environment and individual time constraints; to assess people’s food choices in relation to food environmental exposure; and to examine the moderating role of individual and contextual determinants of food purchases and consumption.

Methods

We conducted a 7-day observational study among adults (25-45 years of age) living in urban areas in the Netherlands. Participants completed a baseline questionnaire, used an app (incorporating global positioning system tracking and ecological momentary assessment) for 7 days, and then completed a closing survey. The app automatically collected global positioning system tracking data, and participants uploaded information on all food purchases over the 7-day period into the app. Participants also answered questions on contextual or individual purchase-related determinants directly after each purchase. During the final 3 days of the study, the participants also uploaded data on fruit, vegetable, and snack consumption and answered similar ecological momentary assessment questions after each intake.

Results

In total, 140 participants completed the study. More than half of the participants said they liked the app (81/140, 57.9%) and found it easy to use (75/140, 53.6%). Of the 140 participants, 126 (90.0%) said that they had collected data on all or almost all purchases and intakes during the 7-day period. Most found the additional ecological momentary assessment questions “easy to answer” (113/140, 80.7%) with “no effort” (99/140, 70.7%). Of 106 participants who explored their trips in the app, 20 (18.8%) had trouble with their smartphone’s global positioning system tracking function. Therefore, we will not be able to include all participants in some of the proposed analyses, as we lack these data. We are analyzing data from the first study aim and we expect to publish the results in the spring of 2020.

Conclusions

Participants perceived the FoodTrack app as a user-friendly tool. The app is particularly useful for observational studies that aim to gain insight into daily food environment exposure and food choices. Further analyses of the FoodTrack study data will provide novel insights into individual food environmental exposure, evidence on the individual food environment-diet interaction, and insights into the underlying individual and contextual mechanisms of food purchases and consumption.

International Registered Report Identifier (IRRID)

DERR1-10.2196/15283

Development of a Teen-Informed Coding Tool to Measure the Power of Food Advertisements

The food-related information environment, comprised of food and beverage advertising within one’s surroundings, is a growing concern for adolescent health given that food marketing disproportionately targets adolescents. Despite strong public interest concerning the effects of food marketing on child health, there is limited evidence focused on outdoor food advertising in relation to teenage diets, food purchasing, and perceptions. Further, limited research has considered both the exposure to and influence of such advertisements. This study used a novel multi-method approach to identify and quantify the features of outdoor food and beverage advertisements that are most effective at drawing teenagers into retail food establishments. An environmental audit of outdoor advertisements and consultations with youth were used to: (1) identify teen-directed food marketing techniques; (2) validate and weigh the power of individual advertising elements; and, (3) develop a teen-informed coding tool to measure the power of food-related advertisements. Results indicate that marketing power is a function of the presence and size of teen-directed advertisement features, and the relative nature of each feature is an important consideration. This study offers a quantitative measurement tool for food environment research and urges policymakers to consider teen-directed marketing when creating healthy communities.

Returning to our roots: The use of geospatial data for nurse-led community research

In the early 20th century, public health nurse, Lillian Wald, addressed the social determinants of health (SDOH) through her work in New York City and her advocacy to improve policy in workplace conditions, education, recreation, and housing. In the early 21st century, addressing the SDOH is a renewed priority and provides nurse researchers with an opportunity to return to our roots. The purpose of this methods paper is to examine how the incorporation of geospatial data and spatial methodologies in community research can enhance the analyses of the complex relationships between social determinants and health. Geospatial technologies, software for mapping and working with geospatial data, statistical methods, and unique considerations are discussed. An exemplar for using geospatial data is presented regarding associations between neighborhood greenspace, neighborhood violence, and children's asthma control. This innovative use of geospatial data illustrates a new frontier in investigating nontraditional connections between the environment and SDOH outcomes.

Mobile Sensing in Environmental Health and Neighborhood Research

Public health research has witnessed a rapid development in the use of location, environmental, behavioral, and biophysical sensors that provide high-resolution objective time-stamped data. This burgeoning field is stimulated by the development of novel multisensor devices that collect data for an increasing number of channels and algorithms that predict relevant dimensions from one or several data channels. Global positioning system (GPS) tracking, which enables geographic momentary assessment, permits researchers to assess multiplace personal exposure areas and the algorithm-based identification of trips and places visited, eventually validated and complemented using a GPS-based mobility survey. These methods open a new space-time perspective that considers the full dynamic of residential and nonresidential momentary exposures; spatially and temporally disaggregates the behavioral and health outcomes, thus replacing them in their immediate environmental context; investigates complex time sequences; explores the interplay among individual, environmental, and situational predictors; performs life-segment analyses considering infraindividual statistical units using case-crossover models; and derives recommendations for just-in-time interventions.

A Time-Based Objective Measure of Exposure to the Food Environment

Exposure to food environments has mainly been limited to counting food outlets near participants’ homes. This study considers food environment exposures in time and space using global positioning systems (GPS) records and fast food restaurants (FFRs) as the environment of interest. Data came from 412 participants (median participant age of 45) in the Seattle Obesity Study II who completed a survey, wore GPS receivers, and filled out travel logs for seven days. FFR locations were obtained from Public Health Seattle King County and geocoded. Exposure was conceptualized as contact between stressors (FFRs) and receptors (participants’ mobility records from GPS data) using four proximities: 21 m, 100 m, 500 m, and ½ mile. Measures included count of proximal FFRs, time duration in proximity to ≥1 FFR, and time duration in proximity to FFRs weighted by FFR counts. Self-reported exposures (FFR visits) were excluded from these measures. Logistic regressions tested associations between one or more reported FFR visits and the three exposure measures at the four proximities. Time spent in proximity to an FFR was associated with significantly higher odds of FFR visits at all proximities. Weighted duration also showed positive associations with FFR visits at 21-m and 100-m proximities. FFR counts were not associated with FFR visits. Duration of exposure helps measure the relationship between the food environment, mobility patterns, and health behaviors. The stronger associations between exposure and outcome found at closer proximities (<100 m) need further research.

Community-engaged development of a GIS-based healthfulness index to shape health equity solutions

Addressing health disparities requires both community engagement and an understanding of the social determinants of health. Although elements of the built environment can influence behavior change in public health interventions, such determinants have not been explicitly teased out via participatory mapping. An opportunity exists to integrate community voice in the development of such metrics. To fill this gap and inform the deployment of public health interventions in the Flint (USA) Center for Health Equity Solutions (FCHES), we created a means of assessing spatially-varying community needs and assets in a geographic information system (GIS), what we refer to as a healthfulness index. We engaged community and academic partners in their expert opinions on features of Flint's built environment that may promote or inhibit healthy behaviors via a multiple-criteria decision analysis framework. Experts selected from and ranked 29 variables in 6 categories (including amenities, environment, greenspace, housing, infrastructure, and social issues) using the analytic hierarchy process. The resulting matrices of expert opinions were aggregated and appended as weights for each variable's corresponding map layer. When combined through map algebra, composite scores yield spatially-varying healthfulness indices which signal any neighborhood's relative health promoting qualities (along a 0-100 scale). Results varied substantially across Flint, with the middle belt scoring highest and older neighborhoods in the northeast and north center of the city scoring lowest. Scores were aggregated to 38 Flint neighborhoods; for each of two project-specific indices, these ranged from lows of 38.7 (Hilborn Park) and 41.8 (Columbia Heights) to highs of 52.9 (College Cultural) and 58.0 (University Ave Corridor). We hypothesize that-even when controlling for individual-level factors-we will measure better and more sustained behavior change among participants living in neighborhoods with high healthfulness scores. Future work will examine this hypothesis and determine the importance of such indices in other similar communities.

Children's mobility and environmental exposures in urban landscapes: A cross-sectional study of 10-11 year old Scottish children

Research into how the environment affects health and related behaviour is typically limited in at least two ways: it represents the environment to which people are exposed using fixed areal units, and, it focuses on one or two environmental characteristics only. This study developed a methodology for describing children's mobility and the complexity of their environmental exposure across a 1934 km2 study area, including urban, suburban and rural zones. It conceptualised and modelled this area as a landscape, comprised of spatially discrete amenities, infrastructure features, differing land covers/use and broader environmental contexts. The model used a 25 m2 grid system (∼3 million cells). For each cell, there was detailed built-environment information. We joined data for 100 10/11-year-old children who had worn GPS trackers to provide individual-level mobility information for one week during 2015/16 to our model. Using negative binomial regression, we explored which landscape features were associated with a child visiting that space and time spent there. We examined whether relationships between the features across our study area and children's use of the space differed by their sociodemographic characteristics. We found that children often used specific amenities outside their home neighbourhood, even if they were also available close to home. They spent more time in cells containing roads/transportation stops, food/drink retail (Incidence rate ratio (IRR):4.02, 95%CI 2.33 to 6.94), places of worship (IRR:5.98, 95%CI 3.33 to 10.72) and libraries (IRR:7.40, 95%CI 2.13 to 25.68), independently of proximity to home. This has importance for the optimal location of place-based health interventions. If we want to target children, we need to understand that using fixed neighbourhood boundaries may not be the best way to do it. The variations we found in time spent in certain areas by sex and socio-economic position also raise the possibility that interventions which ignore these differences may exacerbate inequalities.

A comparative analysis of the restaurant consumer food environment in Rochester (NY, USA) and London (ON, Canada): assessing children's menus by neighbourhood socio-economic characteristics

OBJECTIVE

To assess restaurant children's menus for content and nutritional quality; and to investigate the relationship between the restaurant consumer food environment for children and neighbourhood-level socio-economic characteristics within and between one Canadian city and one US city.

DESIGN

Cross-sectional observational study.

SETTING

London, ON, Canada and Rochester, NY, USA.ParticipantsRestaurant children's menus were assessed, scored and compared using the Children's Menu Assessment tool. We quantified neighbourhood accessibility to restaurants by calculating 800 m road-network buffers around the centroid of each city census block and created a new Neighbourhood Restaurant Quality Index for Children (NRQI-C) comprising the sum of restaurant menu scores divided by the total number of restaurants within each area. After weighting by population, we examined associations between NRQI-C and neighbourhood socio-economic characteristics using correlations and multiple regression analyses.

RESULTS

Nutritional quality of children's menus was greater, on average, in Rochester compared with London. Only one variable remained significant in the regression analyses for both cities: proportion of visible minorities had a positive effect on neighbourhood NRQI-C scores in London, whereas the reverse was true in Rochester.

CONCLUSIONS

Results suggest the presence of a socio-economic disparity within Rochester, where children in more disadvantaged areas have poorer access to better nutritional quality restaurant choices. In London, results suggest an inverse relationship across the city where children in more disadvantaged areas have better access to better nutritional quality restaurant choices. Given these disparate results, research on restaurant nutritional quality for children requires additional consideration.

Comparing Physical Activity Behavior of Children During School Between Balanced and Traditional School Day Schedules

BACKGROUND

Some Canadian schools have modified their daily schedules from the traditional school day (TSD) schedule (two 15-minute breaks and one 60-minute break) to a balanced school day (BSD) schedule (two 40-minute breaks). While this change increases daily planning and instructional time, it also changes the amount of time available for moderate-vigorous physical activity (MVPA).

METHODS

This study uses a case-control design to examine differences in objectively measured MVPA between children in 3 schools using a BSD schedule and 3 schools using a TSD schedule. Study participants (aged 10-12 years) were recruited from schools in Ontario, Canada.

RESULTS

Regardless of schedule type, girls had lower MVPA than boys, and as both boys and girls got older their MVPA significantly decreased. The findings indicate there was no statistically significant difference in the total minutes of in-school MVPA between children from BSD schools and children from TSD schools. MVPA was significantly higher for older girls attending BSD schools than older girls attending TSD schools, suggesting that implementing a BSD may help curb declining MVPA as girls enter adolescence.

CONCLUSION

Despite encouraging findings, more rigorous studies (ie, pre-post experiments with control) are needed to better understand how changing schedules impacts children's health.

Conceptualizing Youth Participation in Children's Health Research: Insights from a Youth-Driven Process for Developing a Youth Advisory Council

Given the power asymmetries between adults and young people, youth involvement in research is often at risk of tokenism. While many disciplines have seen a shift from conducting research on youth to conducting research with and for youth, engaging children and teens in research remains fraught with conceptual, methodological, and practical challenges. Arnstein's foundational Ladder of Participation has been adapted in novel ways in youth research, but in this paper, we present a new rendering: a 'rope ladder.' This concept came out of our youth-driven planning process to develop a Youth Advisory Council for the Human Environments Analysis Laboratory, an interdisciplinary research laboratory focused on developing healthy communities for young people. As opposed to a traditional ladder, composed of rigid material and maintaining a static position, the key innovation of our concept is that it integrates a greater degree of flexibility and mobility by allowing dynamic movement beyond a 2D vertical plane. At the same time, the pliable nature of the rope makes it both responsive and susceptible to exogenous forces. We argue that involving youth in the design of their own participatory framework reveals dimensions of participation that are important to youth, which may not be captured by the existing participatory models.

More than Fast Food: Development of a Story Map to Compare Adolescent Perceptions and Observations of Their Food Environments and Related Food Behaviors

The purpose of this convergent, multiphase, mixed methods study was to better understand the perceptions of adolescents' food environments and related food behaviors using grounded visualization and story mapping. Adolescents from one high school (13⁻16 years) in the southeastern United States were evaluated via data from health behavior surveys (n = 75), school environment maps, focus groups (n = 5 groups), and Photovoice (n = 6) from October 2016 to April 2017. Data from each phase were integrated using grounded visualization and new themes were identified (n = 7). A story map using ArcGIS Online was developed from data integration, depicting the newly identified themes. Participants failed to meet national recommendations for fruit and vegetable intake (2.71 cups). Focus group and Photovoice findings indicated the need for convenience food items in all environments. The story map is an online, interactive dissemination of information, with five maps, embedded quotes from focus groups, narrative passages with data interpretation, pictures to highlight themes, and a comparison of the participants' food environments. Story mapping and qualitative geographic information systems (GIS) approaches may be useful when depicting adolescent food environments and related food behaviors. Further research is needed when evaluating story maps and how individuals can be trained to create their own maps.

Are disadvantaged children more likely to be excluded from analysis when applying global positioning systems inclusion criteria?

Objective

When using global positioning systems (GPS) to assess an individual’s exposure to their environment, a first step in data cleaning is to establish minimum GPS ‘inclusion criteria’ (a set of rules used to determine which GPS data are able to be included in analyses). Care is needed at this stage to avoid any data exclusion (data loss) systematically biasing results in terms of characteristics of the environment and participants. The extent of potential systematic bias in sample retention due to GPS data loss and application of GPS inclusion criteria is unknown. The aim of this study was to describe differences in sample size and socio-demographic characteristics of the retained sample when applying three different GPS inclusion criteria. The study assessed 7-day GPS data collected from children (aged 9–13 years) recruited from nine schools in Auckland, New Zealand as part of the Kids in the City study.

Results

Participants from ethnic minorities and those attending schools in lower socioeconomic areas were disproportionately excluded from the retained samples. This highlights potential equity implications in basing the assessment of exposure—which ultimately influences research results on the relationship between environment and health—on non-representative GPS data.

Associations between home and school neighbourhood food environments and adolescents’ fast-food and sugar-sweetened beverage intakes: findings from the Olympic Regeneration in East London (ORiEL) Study

Objective

To examine associations between availability of fast-food restaurants and convenience stores in the home and school neighbourhoods, considered separately and together, and adolescents’ fast-food and sugar-sweetened beverage (SSB) intakes.

Design

Cross-sectional observational study.

Setting

East London, UK.

Subjects

Adolescents (n3089; aged 13–15 years) from the Olympic Regeneration in East London (ORiEL) Study self-reported their weekly frequency of fast-food and SSB consumption. We used food business addresses collected from local authority registers to derive absolute (counts) and relative (proportions) exposure measures to fast-food restaurants and convenience stores within 800 m from home, school, and home and school combined. Associations between absolute and relative measures of the food environment and fast-food and SSB intakes were assessed using Poisson regression models with robust standard errors.

Results

Absolute exposure to fast-food restaurants or convenience stores in the home, school, or combined home and school neighbourhoods was not associated with any of the outcomes. High SSB intake was associated with relative exposure to convenience stores in the residential neighbourhood (risk ratio=1·45; 95 % CI 1·08, 1·96) and in the home and school neighbourhoods combined (risk ratio=1·69; 95 % CI 1·11, 2·57).

Conclusions

We found no evidence of an association between absolute exposure to fast-food restaurants and convenience stores around home and school and adolescents’ fast-food and SSB intakes. Relative exposure, which measures the local diversity of the neighbourhood food environment, was positively associated with SSB intake. Relative measures of the food environment may better capture the environmental risks for poor diet than absolute measures.

Examining community and consumer food environments for children: An urban-suburban-rural comparison in Southwestern Ontario

The aim of this study is to evaluate how retail food environments for children in the City of London and Middlesex County, Ontario, Canada, vary according to level of urbanicity and level of socioeconomic distress. Urbanicity in this study is defined as a neighbourhood's designation as urban, suburban, or rural. We assessed community food environments (e.g., the type, location, and accessibility of food outlets) using 800m and 1600m network buffers (school zones) around all public and private elementary schools, and we calculated and compared density of junk food opportunities (JFO) (e.g., fast food and full-service restaurants, grocery stores, and convenience stores) within each school zone in urban, suburban and rural settings. The study also assessed consumer food environments (e.g., the price, promotion, placement, and availability of healthy options and nutrition information) through restaurant children's menu audits using the Children's Menu Assessment tool. Results suggest JFO density is greater around elementary schools in areas with higher levels of socioeconomic distress and urbanicity, while urbanicity is also associated with greater use of branded marketing and inclusion of an unhealthy dessert on children's menus.

User acceptance of location-tracking technologies in health research: Implications for study design and data quality

Research regarding place and health has undergone a revolution due to the availability of consumer-focused location-tracking devices that reveal fine-grained details of human mobility. Such research requires that participants accept such devices enough to use them in their daily lives. There is a need for a theoretically grounded understanding of acceptance of different location-tracking technology options, and its research implications. Guided by an extended Unified Theory of Acceptance and Use of Technology (UTAUT), we conducted a 28-day field study comparing 21 chronically ill people's acceptance of two leading, consumer-focused location-tracking technologies deployed for research purposes: (1) a location-enabled smartphone, and (2) a GPS watch/activity tracker. Participants used both, and completed two surveys and qualitative interviews. Findings revealed that all participants exerted effort to facilitate data capture, such as by incorporating devices into daily routines and developing workarounds to keep devices functioning. Nevertheless, the smartphone was perceived to be significantly easier and posed fewer usability challenges for participants than the watch. Older participants found the watch significantly more difficult to use. For both devices, effort expectancy was significantly associated with future willingness to participate in research although prosocial motivations overcame some concerns. Social influence, performance expectancy and use behavior were significantly associated with intentions to use the devices in participants' personal lives. Data gathered via the smartphone was significantly more complete than data gathered via the watch, primarily due to usability challenges. To make longer-term participation in location tracking research a reality, and to achieve complete data capture, researchers must minimize the effort involved in participation; this requires usable devices. For long-term location-tracking studies using similar devices, findings indicate that only smartphone-based tracking is up to the challenge.

The Flint Food Store Survey: combining spatial analysis with a modified Nutrition Environment Measures Survey in Stores (NEMS-S) to measure the community and consumer nutrition environments

OBJECTIVE

The goal of the present study was to use a methodology that accurately and reliably describes the availability, price and quality of healthy foods at both the store and community levels using the Nutrition Environment Measures Survey in Stores (NEMS-S), to propose a spatial methodology for integrating these store and community data into measures for defining objective food access.

SETTING

Two hundred and sixty-five retail food stores in and within 2 miles (3·2 km) of Flint, Michigan, USA, were mapped using ArcGIS mapping software.

DESIGN

A survey based on the validated NEMS-S was conducted at each retail food store. Scores were assigned to each store based on a modified version of the NEMS-S scoring system and linked to the mapped locations of stores. Neighbourhood characteristics (race and socio-economic distress) were appended to each store. Finally, spatial and kernel density analyses were run on the mapped store scores to obtain healthy food density metrics.

RESULTS

Regression analyses revealed that neighbourhoods with higher socio-economic distress had significantly lower dairy sub-scores compared with their lower-distress counterparts (β coefficient=-1·3; P=0·04). Additionally, supermarkets were present only in neighbourhoods with <60 % African-American population and low socio-economic distress. Two areas in Flint had an overall NEMS-S score of 0.

CONCLUSIONS

By identifying areas with poor access to healthy foods via a validated metric, this research can be used help local government and organizations target interventions to high-need areas. Furthermore, the methodology used for the survey and the mapping exercise can be replicated in other cities to provide comparable results.

You are where you live: Methodological challenges to measuring children's exposure to hazards

Many of the challenges that affect children living in poverty are directly related to the neighborhoods in which they live. Places that inhibit healthy living and those that expose children to environmental pollution tend to more heavily affect children in poverty. This environmental injustice is a natural concern of the fields of urban planning, geography, and children's health. Yet many decisions that affect opportunities for healthy living are made without a full understanding of how neighborhood context influences such opportunities. In this brief, we paint inequalities in child health outcomes as a spatial problem, review some of the geospatial tools used by urban planners and geographers, discuss common reasons for misclassification or misrepresentation of spatially explicit problems, and propose more suitable methods for measuring opportunities and exposures germane to the field of child poverty. Throughout, we emphasize the need for evidence-driven, spatially grounded responses to child poverty issues with a spatial dimension.

Charting Availability of Processed and Unprocessed Foods in School Neighbourhood Nutrition Environments in an Urban Australian Setting

School Neighbourhood Nutrition Environments (SNNEs) can facilitate or impede healthy eating. This study describes the SNNEs surrounding 6 Good Start Program (GSP) schools in 5 suburbs in Logan, Queensland. Relative density of healthy and unhealthy food outlets was calculated for SNNEs surrounding GSP (6) and non-GSP (10) schools within the 5 suburbs. Relative accessibility of minimally processed and highly processed food and drink in SNNEs of the 6 GSP schools was determined using shelf measurements of snack foods. Unhealthy outlets greatly outnumber healthy outlets (mean relative density 15.6%, median 19.1%). The majority of outlets stock predominantly highly processed food and drink. Study areas are dominated by unhealthy food outlets and highly processed food.

Where do people purchase food? A novel approach to investigating food purchasing locations

Background

Studies exploring associations between food environments and food purchasing behaviours have been limited by the absence of data on where food purchases occur. Determining where food purchases occur relative to home and how these locations differ by individual, neighbourhood and trip characteristics is an important step to better understanding the association between food environments and food behaviours.

Methods

Conducted in Melbourne, Australia, this study recruited participants within sixteen neighbourhoods that were selected based on their socioeconomic characteristics and proximity to supermarkets. The survey material contained a short questionnaire on individual and household characteristics and a food purchasing diary. Participants were asked to record details related to all food purchases made over a 2-week period including food store address. Fifty-six participants recorded a total of 952 food purchases of which 893 were considered valid for analysis. Households and food purchase locations were geocoded and the network distance between these calculated. Linear mixed models were used to determine associations between individual, neighbourhood, and trip characteristics and distance to each food purchase location from home. Additional analysis was conducted limiting the outcome to: (a) purchase made when home was the prior origin (n. 484); and (b) purchases made within supermarkets (n. 317).

Results

Food purchases occurred a median distance of 3.6 km (IQR 1.8, 7.2) from participants’ homes. This distance was similar when home was reported as the origin (median 3.4 km; IQR 1.6, 6.4) whilst it was shorter for purchases made within supermarkets (median 2.8 km; IQR 1.6, 5.6). For all purchases, the reported food purchase location was further from home amongst the youngest age group (compared to the oldest age group), when workplace was the origin of the food purchase trip (compared to home), and on weekends (compared to weekdays). Differences were also observed by neighbourhood characteristics.

Conclusions

This study has demonstrated that many food purchases occur outside what is traditionally considered the residential neighbourhood food environment. To better understand the role of food environments on food purchasing behaviours, further work is needed to develop more appropriate food environment exposure measures.

Electronic supplementary material

The online version of this article (doi:10.1186/s12942-017-0082-z) contains supplementary material, which is available to authorized users.