Quantifying time spent outdoors: A versatile method using any type of global positioning system (GPS) and accelerometer devices.

Spending time outdoors is associated with increased time spent in physical activity, lower chronic disease risk, and wellbeing. Many studies rely on self-reported measures, which are prone to recall bias. Other methods rely on features and functions only available in some GPS devices. Thus, a reliable and versatile method to objectively quantify time spent outdoors is needed. This study sought to develop a versatile method to classify indoor and outdoor (I/O) GPS data that can be widely applied using most types of GPS and accelerometer devices. To develop and test the method, five university students wore an accelerometer (ActiGraph wGT3X-BT) and a GPS device (Canmore GT-730FL-S) on an elastic belt at the right hip for two hours in June 2022 and logged their activity mode, setting, and start time via activity diaries. GPS trackers were set to collect data every 5 seconds. A rule-based point cluster-based method was developed to identify indoor, outdoor, and in-vehicle time. Point clusters were detected using an application called GPSAS_Destinations and classification were done in R using accelerometer lux, building footprint, and park location data. Classification results were compared with the submitted activity diaries for validation. A total of 7,006 points for all participants were used for I/O classification analyses. The overall I/O GPS classification accuracy rate was 89.58% (Kappa = 0.78), indicating good classification accuracy. This method provides reliable I/O clarification results and can be widely applied using most types of GPS and accelerometer devices.

A Critical Appraisal of a University's Response to a Campus Mass Shooting: Perspectives from Public Health Students and Researchers at Michigan State University.

Mass shootings are a public health crisis and have become more frequent on U.S. university campuses over the past decade, with the number doubling since 2000. Due to this alarming trend, many institutions have developed response strategies for active shooting events. Yet, the extent to which these response strategies address the needs and minimize harm for students, faculty, and staff has not been evaluated critically after a campus mass shooting. Michigan State University (MSU) experienced a mass shooting on February 13, 2023. Before, during, and 6 months following this tragedy, the university employed an estimated 18 strategies to inform, support, and protect its students, faculty, and staff. While MSU continues to address concerns and roll out programs related to this event, here we aimed to (1) create a timeline of resources and communication provided by MSU from the event to 6 months post-event; (2) critically evaluate the extent to which these resources met the needs of students, faculty, and staff through a survey among persons involved in public health research; and (3) identify potential areas for improvement in the university's responses. We used an online survey where participants (n = 10) rated the university responses and provided additional comments. From our survey, we recommend that, in the event of a campus shooting, other universities are attentive to re-engaging with the community within which the university is situated, holding communal events on campus, offering pauses in classes, and enhancing mental health services. These responses were seen as crucial to re-establish campus life and learning.

Water Supply Interruptions Are Associated with More Frequent Stressful Behaviors and Emotions but Mitigated by Predictability: A Multisite Study.

Water supply interruptions contribute to household water insecurity. Unpredictable interruptions may particularly exacerbate water insecurity, as uncertainty limits households' ability to optimize water collection and storage or to modify other coping behaviors. This study used regression models of survey data from 2873 households across 10 sites in 9 middle-income countries to assess whether water supply interruptions and the predictability of interruptions were related to composite indicators of stressful behaviors and emotional distress. More frequent water service interruptions were associated with more frequent emotional distress (ß = 0.49, SE = 0.05, P < 0.001) and stressful behaviors (ß = 0.39, SE = 0.06, P < 0.001). Among households that experienced interruptions, predictability mitigated these respective relationships by approximately 25 and 50%. Where the provision of continuous water supplies is challenged by climate change, population growth, and poor management, water service providers may be able to mitigate some psychosocial consequences of intermittency through scheduled intermittency and communication about water supply interruptions. Service providers unable to supply continuous water should optimize intermittent water delivery to reduce negative impacts on users, and global monitoring regimes should account for intermittency and predictability in post-2030 water service metrics to better reflect household water insecurity experiences.

Comparison of ten policy options to equitably reduce children's exposure to unhealthy food marketing.

OBJECTIVE: Reducing children's exposure to unhealthy food marketing is crucial to combat childhood obesity. We aimed to estimate the reduction of children's exposure to food marketing under different policy scenarios and assess exposure differences by socio-economic status. DESIGN: Data on children's exposure to unhealthy food marketing were compiled from a previous cross-sectional study in which children (n 168) wore wearable cameras and Global Positioning System (GPS) units for 4 consecutive days. For each exposure, we identified the setting, the marketing medium and food/beverage product category. We analysed the percentage reduction in food marketing exposure for ten policy scenarios and by socio-economic deprivation: (1) no product packaging, (2) no merchandise marketing, (3) no sugary drink marketing, (4) no confectionary marketing in schools, (5) no sugary drink marketing in schools, (6) no marketing in public spaces, (7) no marketing within 400 m of schools, (8) no marketing within 400 m of recreation venues, (9) no marketing within 400 m of bus stops and (10) no marketing within 400 m of major roads. SETTING: Wellington region of New Zealand. PARTICIPANTS: 168 children aged 11-14 years. RESULTS: Exposure to food marketing varied by setting, marketing medium and product category. Among the ten policy scenarios, the largest reductions were for plain packaging (60·3 %), no sugary drink marketing (28·8 %) and no marketing in public spaces (22·2 %). There were no differences by socio-economic deprivation. CONCLUSIONS: The results suggest that plain packaging would result in the greatest decrease in children's exposure to food marketing. However, given that children are regularly exposed to unhealthy food marketing in multiple settings through a range of marketing mediums, comprehensive bans are needed to protect children's health.

Dementia, dementia's risk factors and premorbid brain structure are concentrated in disadvantaged areas: National register and birth-cohort geographic analyses.

INTRODUCTION: Dementia risk may be elevated in socioeconomically disadvantaged neighborhoods. Reasons for this remain unclear, and this elevation has yet to be shown at a national population level. METHODS: We tested whether dementia was more prevalent in disadvantaged neighborhoods across the New Zealand population (N = 1.41 million analytic sample) over a 20-year observation. We then tested whether premorbid dementia risk factors and MRI-measured brain-structure antecedents were more prevalent among midlife residents of disadvantaged neighborhoods in a population-representative NZ-birth-cohort (N = 938 analytic sample). RESULTS: People residing in disadvantaged neighborhoods were at greater risk of dementia (HR per-quintile-disadvantage-increase = 1.09, 95% confidence interval [CI]:1.08-1.10) and, decades before clinical endpoints typically emerge, evidenced elevated dementia-risk scores (CAIDE, LIBRA, Lancet, ANU-ADRI, DunedinARB; ß's 0.31-0.39) and displayed dementia-associated brain structural deficits and cognitive difficulties/decline. DISCUSSION: Disadvantaged neighborhoods have more residents with dementia, and decades before dementia is diagnosed, residents have more dementia-risk factors and brain-structure antecedents. Whether or not neighborhoods causally influence risk, they may offer scalable opportunities for primary dementia prevention.

Child effects on positive parenting vary with neighborhood opportunity.

Prior theoretical and empirical research has highlighted links between positive parenting and the socioeconomic characteristics of the family's neighborhood, but has yet to illuminate the etiologic origins of this association. One possibility is that the various predictors of parenting outlined by Belsky (1984; e.g., characteristics of the child, characteristics of the parent, and contextual influences) may matter more in some neighborhood contexts than in others. To examine this possibility, we conducted etiologic moderation analyses in a sample of 1,030 families of twins (average age 8 years; 51% male, 49% female; racial composition: 82% White, 10% Black, 1% Asian, 1% Indigenous, and 6% multiracial) from the Twin Study of Behavioral and Emotional Development in Children in the Michigan State University Twin Registry. Neighborhood and parenting were assessed using multiple informants and assessment strategies (neighborhood and family informants, administrative data, and videotaped parent-child interactions). Results pointed to strong evidence of etiologic moderation, such that child effects on positive mothering were prominent in neighborhoods with little opportunity and near zero in neighborhoods with ample opportunity. Such findings not only reframe the magnitude of child effects on the parenting they receive as context-dependent, but also indicate that mothers in impoverished neighborhoods may be more responsive to their children's characteristics than mothers in neighborhoods with ample opportunity. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Neighborhood features moderate genetic and environmental influences on children's social information processing.

Neighborhood is a key context where children learn to process social information; however, the field has largely overlooked the ways children's individual characteristics might be moderated by neighborhood effects. We examined 1,030 six- to 11-year-olds (48.7% female; 82% White) twin pairs oversampled for neighborhood disadvantage from the Twin Study of Behavioral and Emotional Development in Children. We evaluated neighbor reports (N = 1,880) of neighborhood structural and social characteristics as moderators of genetic and environmental influences on children's social processing. Although there was no evidence of moderation for children's hostile attributions, there was robust evidence that the social and structural characteristics of the neighborhood moderated the genetic and environmental origins of children's positive expectations of aggressive behavior. Specifically, we found that genetic influences on aggressive expectations increased in the presence of neighborhood deprivation and decreased in the presence of protective social processes and availability of resources. Such findings suggest that protective neighborhood social processes may buffer against the development of aggressive expectations during middle childhood by suppressing the expression of genetic influences on those outcomes. In doing so, they suggest that neighborhood social processes may be able to promote youth resilience to neighborhood deprivation "under the skin." (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Systematic review of best practices for GPS data usage, processing, and linkage in health, exposure science and environmental context research.

Global Positioning System (GPS) technology is increasingly used in health research to capture individual mobility and contextual and environmental exposures. However, the tools, techniques and decisions for using GPS data vary from study to study, making comparisons and reproducibility challenging. OBJECTIVES: The objectives of this systematic review were to (1) identify best practices for GPS data collection and processing; (2) quantify reporting of best practices in published studies; and (3) discuss examples found in reviewed manuscripts that future researchers may employ for reporting GPS data usage, processing and linkage of GPS data in health studies. DESIGN: A systematic review. DATA SOURCES: Electronic databases searched (24 October 2023) were PubMed, Scopus and Web of Science (PROSPERO ID: CRD42022322166). ELIGIBILITY CRITERIA: Included peer-reviewed studies published in English met at least one of the criteria: (1) protocols involving GPS for exposure/context and human health research purposes and containing empirical data; (2) linkage of GPS data to other data intended for research on contextual influences on health; (3) associations between GPS-measured mobility or exposures and health; (4) derived variable methods using GPS data in health research; or (5) comparison of GPS tracking with other methods (eg, travel diary). DATA EXTRACTION AND SYNTHESIS: We examined 157 manuscripts for reporting of best practices including wear time, sampling frequency, data validity, noise/signal loss and data linkage to assess risk of bias. RESULTS: We found that 6% of the studies did not disclose the GPS device model used, only 12.1% reported the per cent of GPS data lost by signal loss, only 15.7% reported the per cent of GPS data considered to be noise and only 68.2% reported the inclusion criteria for their data. CONCLUSIONS: Our recommendations for reporting on GPS usage, processing and linkage may be transferrable to other geospatial devices, with the hope of promoting transparency and reproducibility in this research. PROSPERO REGISTRATION NUMBER: CRD42022322166.

A systematic review of audit tools for evaluating the quality of green spaces in mental health research.

Research showing the relationship between exposure to green space and health has yielded conflicting results, possibly due to the oversight of green space quality in quantitative studies. This systematic review, guided by the PRISMA framework (registered under Prospero ID CRD42023279720), focused on audit tools for green space quality in mental health research. From 4028 studies, 13 were reviewed, with 77 % linking better mental health outcomes to higher green space quality. Eight tools, especially Public Open Space and Dillen et al. tools demonstrated strong correlations with mental health. Certain green space qualities like grass, pathways, and water elements showed positive health associations. Future research should aim for standardized quality metrics and robust methodologies to support causal inferences and efficient assessments.

Four recommendations to tackle the complex reality of transdisciplinary, natural experiment research.

Natural experiments are often used to study interventions in which randomization to control versus intervention conditions are impossible. Nature-based interventions (i.e., programs designed to increase human interaction with nature and improve human health) are commonly studied as natural experiments. We used a natural experiment design to explore the benefits of ecological rehabilitation of parks on biodiversity and resident health in low-income, minoritized neighborhoods in Detroit, MI. Given the complexities and interconnectedness of lived experiences, community needs, and ecological health, this research design has presented challenges. Based on our experiences, we pose four key recommendations for researchers and practitioners conducting natural experiments, nature-based interventions, and those working in low-income, minoritized neighborhoods. We use the explicit examples of challenges faced as rationale for these recommendations. The key recommendations are (1) Engage with community leaders; (2) Build a transdisciplinary team and work closely; (3) Examine privilege; and (4) Create a unified vision.

The effects of contemporary redlining on the mental health of Black residents.

Understanding how structural racism, including institutionalized practices such as redlining, influence persistent inequities in health and neighborhood conditions is still emerging in urban health research. Such research often focuses on historical practices, giving the impression that such practices are a thing of the past. However, mortgage lending bias can be readily detected in contemporary datasets and is an active form of structural racism with implications for health and wellbeing. The objective of the current study was to test for associations among multiple measures of mental health and a measure of contemporary redlining. We linked a redlining index constructed using Home Mortgage Disclosure Act data (2007-2013) to 2021 health data for Black/African American participants in the Study of Active Neighborhoods in Detroit (n = 220 with address data). We used multilevel regression models to examine the relationship between redlining and a suite of mental health outcomes (perceived stress, anxiety, depressive symptoms, and satisfaction with life), accounting for covariates including racial composition of the neighborhood. We considered three mediating factors: perceived neighborhood cohesion, aesthetics, and discrimination. Although all participants lived in redlined neighborhoods compared to the complete Detroit Metropolitan area, participants with very low income, low levels of experienced discrimination, and lower perceptions of neighborhood aesthetics resided in highly redlined neighborhoods (score ≥5). We observed that higher resident-reported neighborhood aesthetics were found in neighborhoods with lower redlining scores and were associated with higher levels of satisfaction with life. We found that lower levels of redlining were significantly associated with higher levels of perceived discrimination, which was significantly, positively associated with anxiety, depressive symptoms, and perceived stress scores. Our findings highlight that contemporary redlining practices may influence the aesthetics of the built environment because these neighborhoods experience less investment, with implications for residents' satisfaction with life. However, areas with lower redlining may be areas where Black/African American people experience increased perceived discrimination.

Elementary Classroom Views of Nature Are Associated with Lower Child Externalizing Behavior Problems.

Exposure to nature views has been associated with diverse mental health and cognitive capacity benefits. Yet, much of this evidence was derived in adult samples and typically only involves residential views of nature. Findings from studies with children suggest that when more greenness is available at home or school, children have higher academic performance and have expedited attention restoration, although most studies utilize coarse or subjective assessments of exposure to nature and largely neglect investigation among young children. Here, we investigated associations between objectively measured visible nature at school and children's behavior problems (attention and externalizing behaviors using the Brief Problem Monitor Parent Form) in a sample of 86 children aged seven to nine years old from 15 classrooms across three schools. Images of classroom windows were used to quantify overall nature views and views of specific nature types (sky, grass, tree, shrub). We fitted separate Tobit regression models to test associations between classroom nature views and attention and externalizing behaviors, accounting for age, sex, race/ethnicity, residential deprivation score, and residential nature views (using Google Street View imagery). We found that higher levels of visible nature from classroom windows were associated with lower externalizing behavior problem scores, after confounder adjustment. This relationship was consistent for visible trees, but not other nature types. No significant associations were detected for attention problems. This initial study suggests that classroom-based exposure to visible nature, particularly trees, could benefit children's mental health, with implications for landscape and school design.

Identifying the 'active ingredients' of socioeconomic disadvantage for youth outcomes in middle childhood.

BACKGROUND: Youth experiencing socioeconomic deprivation may be exposed to disadvantage in multiple contexts (e.g., neighborhood, family, and school). To date, however, we know little about the underlying structure of socioeconomic disadvantage, including whether the 'active ingredients' driving its robust effects are specific to one context (e.g., neighborhood) or whether the various contexts increment one another as predictors of youth outcomes. METHODS: The present study addressed this gap by examining the underlying structure of socioeconomic disadvantage across neighborhoods, families, and schools, as well as whether the various forms of disadvantage jointly predicted youth psychopathology and cognitive performance. Participants were 1,030 school-aged twin pairs from a subsample of the Michigan State University Twin Registry enriched for neighborhood disadvantage. RESULTS: Two correlated factors underlay the indicators of disadvantage. Proximal disadvantage comprised familial indicators, whereas contextual disadvantage represented deprivation in the broader school and neighborhood contexts. Results from exhaustive modeling analyses indicated that proximal and contextual disadvantage incremented one another as predictors of childhood externalizing problems, disordered eating, and reading difficulties, but not internalizing symptoms. CONCLUSIONS: Disadvantage within the family and disadvantage in the broader context, respectively, appear to represent distinct constructs with additive influence, carrying unique implications for multiple behavioral outcomes during middle childhood.

Illuminating Associations between Parenting and Deleterious Neighborhood Characteristics via an Exhaustive Modeling Approach.

Objective: Our goal was to illuminate associations between specific characteristics of under-resourced neighborhoods (i.e., socioeconomic deprivation, danger) and specific aspects of parenting (e.g., parental praise, parental nurturance, harsh parenting, parental control). Background: Prior work has highlighted associations between level of neighborhood disadvantage and the parenting of its residents. However, this work has yet to clarify the specific characteristics of the neighborhood or the types of parenting involved. Method: Exhaustive modelling analyses were conducted in a sample of 1,030 families of twins (average age 8 years; 51% male, 49% female; the racial composition was 82% White, 10% Black, 1% Asian, 1% Indigenous, 6% multiracial) from the Twin Study of Behavioral and Emotional Development in Children. Neighborhood and parenting were assessed using multiple informants and assessment strategies (neighborhood informants, family informants, administrative data, videotaped parent-child interactions). Results: Neighborhood socioeconomic deprivation (i.e., limited institutional and economic structural resources) demonstrated small but consistent associations with positive parenting behaviors and maternal control, but not with negative parenting behaviors. Neighborhood danger (i.e., recorded crime, fear of crime, exposure to community violence), by contrast, demonstrated weaker associations with parenting that dissipated once we controlled for overlap with socioeconomic deprivation. Conclusion: Danger and socioeconomic deprivation do not function as interchangeable characteristics of under-resourced neighborhoods, at least in terms of their association with positive parenting. Future studies should identify the specific mechanisms through which neighborhood socioeconomic deprivation is associated with supportive parenting.

Variations in household water affordability and water insecurity: An intersectional perspective from 18 low- and middle-income countries.

Compounding systems of marginalization differentiate and shape water-related risks. Yet, quantitative water security scholarship rarely assesses such risks through intersectionality, a paradigm that conceptualizes and examines racial, gendered, class, and other oppressions as interdependent. Using an intersectionality approach, we analyze the relationships between household head gender and self-reported socio-economic status, and water affordability (proportion of monthly income spent on water) and water insecurity (a composite measure of 11 self-reported experiences) for over 4000 households across 18 low- and middle-income countries in Central and South America, Africa, and Asia. Interaction terms and composite categorical variables were included in regression models, adjusting for putative confounders. Among households with a high socio-economic status, the proportion of monthly income spent on water differed by household head gender. In contrast, greater household water insecurity was associated with lower socio-economic status and did not meaningfully vary by the gender of the household head. We contextualize and interpret these experiences through larger systems of power and privilege. Overall, our results provide evidence of broad intersectional patterns from diverse sites, while indicating that their nature and magnitude depend on local contexts. Through a critical reflection on the study's value and limitations, including the operationalization of social contexts across different sites, we propose methodological approaches to advance multi-sited and quantitative intersectional research on water affordability and water insecurity. These approaches include developing scale-appropriate models, analyzing complementarities and differences between site-specific and multi-sited data, collecting data on gendered power relations, and measuring the impacts of household water insecurity.

Using linked accelerometer and GPS data for characterizing children's schoolyard physical activity: An overview of hot spot analytic decisions with reporting guidelines.

Hot spot analysis of linked accelerometer and Global Positioning System data is often used to identify areas of high/low activity in the schoolyard. We illustrate the potential impact of a suite of methodological decisions (i) accelerometer metric; (ii) monitor epoch; (iii) number of recess periods/days and level of aggregation; (iv) sample size; (v) distance band; (vi) spatial versus spatiotemporal weighting scheme; and (vii) time band. Accelerometer metrics resulted in different clustering patterns. Longer epochs resulted in a less detailed picture of schoolyard behavior. Level of data aggregation impacted cluster patterns due to inter-period and inter-day differences, but clusters were consistent with increasing sample size. Use of spatiotemporal weight matrices resulted in better separation of hot and cold spots and revealed potentially important temporal clustering patterns. Increasing distance or time band resulted in reallocation of small clusters to larger clusters. Hot spot analysis decisions should be clearly reported in future studies.

Improving risk indexes for Alzheimer's disease and related dementias for use in midlife.

Knowledge of a person's risk for Alzheimer's disease and related dementias (ADRDs) is required to triage candidates for preventive interventions, surveillance, and treatment trials. ADRD risk indexes exist for this purpose, but each includes only a subset of known risk factors. Information missing from published indexes could improve risk prediction. In the Dunedin Study of a population-representative New Zealand-based birth cohort followed to midlife (N = 938, 49.5% female), we compared associations of four leading risk indexes with midlife antecedents of ADRD against a novel benchmark index comprised of nearly all known ADRD risk factors, the Dunedin ADRD Risk Benchmark (DunedinARB). Existing indexes included the Cardiovascular Risk Factors, Aging, and Dementia index (CAIDE), LIfestyle for BRAin health index (LIBRA), Australian National University Alzheimer's Disease Risk Index (ANU-ADRI), and risks selected by the Lancet Commission on Dementia. The Dunedin benchmark was comprised of 48 separate indicators of risk organized into 10 conceptually distinct risk domains. Midlife antecedents of ADRD treated as outcome measures included age-45 measures of brain structural integrity [magnetic resonance imaging-assessed: (i) machine-learning-algorithm-estimated brain age, (ii) log-transformed volume of white matter hyperintensities, and (iii) mean grey matter volume of the hippocampus] and measures of brain functional integrity [(i) objective cognitive function assessed via the Wechsler Adult Intelligence Scale-IV, (ii) subjective problems in everyday cognitive function, and (iii) objective cognitive decline measured as residualized change in cognitive scores from childhood to midlife on matched Weschler Intelligence scales]. All indexes were quantitatively distributed and proved informative about midlife antecedents of ADRD, including algorithm-estimated brain age (ß's from 0.16 to 0.22), white matter hyperintensities volume (ß's from 0.16 to 0.19), hippocampal volume (ß's from -0.08 to -0.11), tested cognitive deficits (ß's from -0.36 to -0.49), everyday cognitive problems (ß's from 0.14 to 0.38), and longitudinal cognitive decline (ß's from -0.18 to -0.26). Existing indexes compared favourably to the comprehensive benchmark in their association with the brain structural integrity measures but were outperformed in their association with the functional integrity measures, particularly subjective cognitive problems and tested cognitive decline. Results indicated that existing indexes could be improved with targeted additions, particularly of measures assessing socioeconomic status, physical and sensory function, epigenetic aging, and subjective overall health. Existing premorbid ADRD risk indexes perform well in identifying linear gradients of risk among members of the general population at midlife, even when they include only a small subset of potential risk factors. They could be improved, however, with targeted additions to more holistically capture the different facets of risk for this multiply determined, age-related disease.

Children's perspectives on the wicked problem of child poverty in Aotearoa New Zealand: a wearable camera study.

AIM: Child poverty is a wicked problem and a key determinant of health, but research on child poverty has relied largely on self-report methods and reports from parents or caregivers. In this study we aimed to assess aspects of child poverty using data collected by children using wearable cameras. METHOD: The Kids'Cam Project recruited 168 randomly selected children aged 11-13 from 16 randomly selected schools in the Wellington Region of Aotearoa New Zealand. Each child wore a wearable camera for four consecutive days, recording an image every seven seconds. We used negative binomial regression models to compare measures of household resources, harms, behaviours and built environment characteristics between children living in low socio-economic deprivation households (n=52) and children living in high socio-economic deprivation households (n=26). RESULTS: Compared with children living in conditions of low socio-economic deprivation, children living in conditions of high socio-economic deprivation captured significantly fewer types of fruit (RR=0.46), vegetables (RR=0.25), educational materials (RR = 0.49) and physical activity equipment (RR = 0.66) on camera. However, they lived in homes with more structural deficiencies (RR=4.50) and mould (no mould was observed in low socio-economic deprivation households). They were also less likely to live in households with fixed heating (RR=0.27) and home computers (RR=0.45), and more likely to consume non-core food outside home (RR=1.94). CONCLUSIONS: The children in this study show that children in poverty face disadvantages across many aspects of their lives. Comprehensive policies are urgently needed to address the complex problem of child poverty.

The distribution of harmful product marketing in public outdoor spaces and the effectiveness of marketing bans.

Children's exposure to the marketing of harmful products in public outdoor spaces may influence their consumption of those products and affect health into adulthood. This study aimed to: i) examine the spatial distribution of children's exposure to three types of marketing-related 'harms' (alcohol, unhealthy food, and gambling) in outdoor spaces in the Wellington region, New Zealand/Aotearoa; ii) compare differences in the distribution of harms by socioeconomic deprivation; and iii) estimate the effectiveness of different policies that ban such marketing. Data were from 122 children aged 11-13y who wore wearable cameras and GPS devices for four consecutive days from July 2014 to June 2015. Images were analysed to identify harmful product marketing exposures in public outdoor spaces. Eight policy scenarios were examined to identify the effectiveness of marketing bans, for all children and by socioeconomic deprivation. Children's ratio of harmful marketing was higher for children from high deprivation households and was also found to cluster, with hots spots observed around city centers. The effectiveness of marketing bans depended on the target setting and ban area, with banning 400 m around bus stops leading to the largest reduction. Effectiveness varied also by type of harm and socioeconomic deprivation. For example, banning alcohol marketing in residential areas was estimated to have a larger effect on exposure reduction for children from high deprivation households. Our findings suggest that alcohol, unhealthy food and gambling marketing often cluster outdoors and that targeted bans of such marketing would likely improve child health and, for some banning scenarios, promote equity.