Spatial Polygamy and Contextual Exposures (SPACEs): Promoting Activity Space Approaches in Research on Place and Health

Affective Sensitivity to Air Pollution (ASAP): Person-specific associations between daily air pollution and affective states

Individuals' sensitivity to climate hazards is a central component of their vulnerability to climate change. In this paper, we introduce and outline the utility of a new intraindividual variability construct, affective sensitivity to air pollution (ASAP)-defined as the extent to which an individual's affective states fluctuate in accordance with daily changes in air quality. As such, ASAP pushes beyond examination of differences in individuals' exposures to air pollution to examination of differences in individuals' sensitivities to air pollution. Building on known associations between air pollution exposure and adverse mental health outcomes, we empirically illustrate how application of Bayesian multilevel models to intensive repeated measures data obtained in an experience sampling study (N = 150) over one year can be used to examine whether and how individuals' daily affective states fluctuate with the daily concentrations of outdoor air pollution in their county. Results indicate construct viability, as we found substantial interindividual differences in ASAP for both affect arousal and affect valence. This suggests that repeated measures of individuals' day-to-day affect provides a new way of measuring their sensitivity to climate change. In addition to contributing to discourse around climate vulnerability, the intraindividual variability construct and methodology proposed here can help better integrate affect and mental health in climate adaptation policies, plans, and programs.

New insights into grocery store visits among east Los Angeles residents using mobility data

In this study, we employed spatially aggregated population mobility data, generated from mobile phone locations in 2021, to investigate patterns of grocery store visits among residents east and northeast of Downtown Los Angeles, in which 60% of the census tracts had previously been designated as "food deserts". Further, we examined whether the store visits varied with neighborhood sociodemographics and grocery store accessibility. We found that residents averaged 0.4 trips to grocery stores per week, with only 13% of these visits within home census tracts, and 40% within home and neighboring census tracts. The mean distance from home to grocery stores was 2.2 miles. We found that people visited grocery stores more frequently when they lived in neighborhoods with higher percentages of Hispanics/Latinos, renters and foreign-born residents, and a greater number of grocery stores. This research highlights the utility of mobility data in elucidating grocery store use, and factors that may facilitate or be a barrier to store access. The results point to limitations of using geographically constrained metrics of food access like food deserts.

GPS-derived environmental exposures during pregnancy and early postpartum - Evidence from the madres cohort

The built and natural environment factors (e.g., greenspace, walkability) are associated with maternal and infant health during and after pregnancy. Most pregnancy studies assess exposures to environmental factors via static methods (i.e., residential location at a single point in time, usually 3rd trimester). These do not capture dynamic exposures encountered in activity spaces (e.g., locations one visits and paths one travels) and their changes over time. In this study, we aimed to compare daily environmental exposure estimates using residential and global positioning systems (GPS)-measured activity space approaches and evaluated potential for exposure measurement error in the former. To do this, we collected four days of continuous geolocation monitoring during the 1st and 3rd trimesters of pregnancy and at 4-6 months postpartum in sixty-two pregnant Hispanic women enrolled in the MADRES cohort. We applied residential and GPS-based methods to assess daily exposures to greenspace, access to parks and transit, and walkability, respectively. We assessed potential for exposure measurement error in residential vs GPS-based estimates using Pearson correlations for each measure overall and by study period. We found residential and GPS-based estimates of daily exposure to total areas of parks and open spaces were weakly positively correlated (r = 0.31, P < .001) across pregnancy and postpartum periods. Residential estimates of %greenspace (r = 0.52, P < .001) and tree cover (r = 0.55, P < .001) along walkable roads were moderately correlated with GPS-based estimates. Residential and GPS-based estimates of public transit proximity, pedestrian-oriented intersection density, and walkability index score were all highly positively correlated (r > 0.70, P < .001). We also found associations between residential and GPS-based estimates decreased among participants with greater daily mobility. Our findings suggest the popular approach that assessing the built and natural environment exposures using residential methods at one time point may introduce exposure measurement error in pregnancy studies. GPS-based methods, to the extent feasible, are recommended for future studies.

Human mobility networks reveal increased segregation in large cities

A long-standing expectation is that large, dense and cosmopolitan areas support socioeconomic mixing and exposure among diverse individuals1-6. Assessing this hypothesis has been difficult because previous measures of socioeconomic mixing have relied on static residential housing data rather than real-life exposures among people at work, in places of leisure and in home neighbourhoods7,8. Here we develop a measure of exposure segregation that captures the socioeconomic diversity of these everyday encounters. Using mobile phone mobility data to represent 1.6 billion real-world exposures among 9.6 million people in the United States, we measure exposure segregation across 382 metropolitan statistical areas (MSAs) and 2,829 counties. We find that exposure segregation is 67% higher in the ten largest MSAs than in small MSAs with fewer than 100,000 residents. This means that, contrary to expectations, residents of large cosmopolitan areas have less exposure to a socioeconomically diverse range of individuals. Second, we find that the increased socioeconomic segregation in large cities arises because they offer a greater choice of differentiated spaces targeted to specific socioeconomic groups. Third, we find that this segregation-increasing effect is countered when a city's hubs (such as shopping centres) are positioned to bridge diverse neighbourhoods and therefore attract people of all socioeconomic statuses. Our findings challenge a long-standing conjecture in human geography and highlight how urban design can both prevent and facilitate encounters among diverse individuals.

Place-Based Developmental Research: Conceptual and Methodological Advances in Studying Youth Development in Context

Scientists have, for some time, recognized that development unfolds in numerous settings, including families, schools, neighborhoods, and organized and unorganized activity settings. Since the turn of the 20th century, the body of mainstream neighborhood effects scholarship draws heavily from the early 20th century Chicago School of Sociology frameworks and have been situating development in neighborhood contexts and working to identify the structures and processes via which neighborhoods matter for a range of developmental outcomes, especially achievement, behavioral and emotional problems, and sexual activity. From this body of work, two new areas of developmental scholarship are emerging. Both areas are promising for advancing an understanding of child development in context. First, cultural-developmental neighborhood researchers are advancing neighborhood effects research that explicitly recognizes the ways that racial, ethnic, cultural, and immigrant social positions matter for neighborhood environments and for youths' developmental demands, affordances, experiences, and competencies. This body of work substantially expands the range of developmental outcomes examined in neighborhood effects scholarship to recognize normative physical, emotional, cognitive, behavioral, social, and cultural competencies that have largely been overlooked in neighborhood effects scholarship that espoused a more color-blind developmental approach. Second, activity space neighborhood researchers are recognizing that residential neighborhoods have important implications for broader activity spaces-or the set of locations and settings to which youth are regularly exposed, including, for example, schools, work, organized activities, and hang-outs. They are using newer technologies and geographic frameworks to assess exposure to residential neighborhood and extra-neighborhood environments. These perspectives recognize that time (i.e., from microtime to mesotime) and place are critically bound and that exposures can be operationalized at numerous levels of the ecological system (i.e., from microsystems to macrosystems). These frameworks address important limitations of prior development in context scholarship by addressing selection and exposure. Addressing selection involves recognizing that families have some degree of choice when selecting into settings and variables that predict families' choices (e.g., income) also predict development. Considering exposure involves recognizing that different participants or residents experience different amounts of shared and nonshared exposures, resulting in both under-and over-estimation of contextual effects. Activity space scholars incorporate exposure to the residential neighborhood environments, but also to other locations and settings to which youth are regularly exposed, like schools, after-school settings, work, and hang-outs. Unfortunately, the cultural-development and activity space streams, which have both emerged from early 20th century work on neighborhood effects on development, have been advancing largely independently. Thus, the overarching aim of this monograph is to integrate scholarship on residential neighborhoods, cultural development, and activity spaces to advance a framework that can support a better understanding of development in context for diverse groups. In Chapters I and II we present the historical context of the three streams of theoretical, conceptual, and methodological research. We also advance a comprehensive cultural-developmental activity space framework for studying development in context among children, youth, and families that are ethnically, racially, and culturally heterogeneous. This framework actively recognized diversity in ethnic, racial, immigrant, and socioeconomic social positions. In Chapters III-V we advance specific features of the framework, focusing on: (1) the different levels of nested and nonnested ecological systems that can be captured and operationalized with activity space methods, (2) the different dimensions of time and exposures or experiences that can be captured and operationalized by activity space methods, and (3) the importance of settings structures and social processes for identifying underlying mechanisms of contextual effects on development. Structures are setting features related to the composition and spatial arrangement of people and institutions (e.g., socioeconomic disadvantage, ethnic/racial compositions). Social processes represent the collective social dynamics that take place in settings, like social interactions, group activities, experiences with local institutions, mechanisms of social control, or shared beliefs. In Chapter VI, we highlight a range of methodological and empirical exemplars from the United States that are informed by our comprehensive cultural-developmental activity space framework. These exemplars feature both quantitative and qualitative methods, including method mixing. These exemplars feature both quantitative and qualitative methods, including method mixing. The exemplars also highlight the application of the framework across four different samples from populations that vary in terms of race, ethnicity, gender, age, socioeconomic status (SES), geographic region, and urbanicity. They capture activity space characteristics and features in a variety of ways, in addition to incorporating family shared and nonshared activity space exposures. Finally, in Chapter VII we summarize the contributions of the framework for advancing a more comprehensive science of development in context, one that better realizes major developmental theories emphasizing persons, processes, contexts, and time. Additionally, we offer a place-based, culturally informed developmental research agenda to meet the needs of an increasingly diverse population.

A Longitudinal Analysis of Residential Mobility and Experience of Client Violence Among Women Who Exchange Sex in Baltimore

Residential mobility remains an underexplored yet critical construct that may influence the risk of violence among women who exchange sex. This study examined the longitudinal relationship between residential mobility and experience of client-perpetrated physical or sexual violence among women who exchange sex in Baltimore, Maryland. Participants were at least at 18 years of age, were cisgender women, reported having engaged in transactional sex three or more times within the last 3 months, and were willing to be contacted for 6-, 12-, and 18-month follow-up visits. Analyses of responses from 370 women who exchange sex participating in at least one study visit were conducted. Unadjusted and adjusted Poisson regression models of the association over time between residential mobility and recent experience of physical or sexual violence were fit. Generalized estimating equations with an exchangeable correlation structure and robust variance estimation were used to account for clustering of participants' responses over time. Findings demonstrated that those who had lived in at least four places in the past 6 months had a 39% increased risk of client-perpetrated physical violence (aRR: 1.39; 95% CI: 1.07-1.80; p < .05) and a 63% increased risk of sexual violence (aRR: 1.63; 95% CI: 1.14-2.32; p < .01) compared to their less-mobile counterparts. These findings provide necessary evidence of correlations over time between residential mobility and experience of client-perpetrated violence among women who exchange sex. Strengthening our understanding of how residential mobility intersects with violence is critical for the development of public health interventions that are relevant to women's lives and needs. Future interventions should explore including residential mobility, a critical pillar of housing instability, with efforts to address client-perpetrated violence.

Novel Location-Based Survey Using Cognitive Interviews to Assess Geographic Networks and Hotspots of Sex and Drug Use: Implementation and Validation Study

BACKGROUND

The Ending the HIV Epidemic initiative in the United States relies on HIV hotspots to identify where to geographically target new resources, expertise, and technology. However, interventions targeted at places with high HIV transmission and infection risk, not just places with high HIV incidence, may be more effective at reducing HIV incidence and achieving health equity.

OBJECTIVE

We described the implementation and validation of a web-based activity space survey on HIV risk behaviors. The survey was intended to collect geographic information that will be used to map risk behavior hotspots as well as the geography of sexual networks in Los Angeles County.

METHODS

The survey design team developed a series of geospatial questions that follow a 3-level structure that becomes more geographically precise as participants move through the levels. The survey was validated through 9 cognitive interviews and iteratively updated based on participant feedback until the saturation of topics and technical issues was reached.

RESULTS

In total, 4 themes were identified through the cognitive interviews: functionality of geospatial questions, representation and accessibility, privacy, and length and understanding of the survey. The ease of use for the geospatial questions was critical as many participants were not familiar with mapping software. The inclusion of well-known places, landmarks, and road networks was critical for ease of use. The addition of a Google Maps interface, which was familiar to many participants, aided in collecting accurate and precise location information. The geospatial questions increased the length of the survey and warranted the inclusion of features to simplify it and speed it up. Using nicknames to refer to previously entered geographic locations limited the number of geospatial questions that appeared in the survey and reduced the time taken to complete it. The long-standing relationship between participants and the research team improved comfort to disclose sensitive geographic information related to drug use and sex. Participants in the cognitive interviews highlighted how trust and inclusive and validating language in the survey alleviated concerns related to privacy and representation.

CONCLUSIONS

This study provides promising results regarding the feasibility of using a web-based mapping survey to collect sensitive location information relevant to ending the HIV epidemic. Data collection at several geographic levels will allow for insights into spatial recall of behaviors as well as future sensitivity analysis of the spatial scale of hotspots and network characteristics. This design also promotes the privacy and comfort of participants who provide location information for sensitive topics. Key considerations for implementing this type of survey include trust from participants, community partners, or research teams to overcome concerns related to privacy and comfort. The implementation of similar surveys should consider local characteristics and knowledge when crafting the geospatial components.

Diversity of Studies on Neighborhood Greenspace and Brain Health by Racialized/Ethnic Group and Geographic Region: A Rapid Review

Studies examining associations between greenspace and Alzheimer's disease and related dementia (ADRD) outcomes are rapidly on the rise, yet no known literature reviews have summarized the racialized/ethnic group and geographic variation of those published studies. This is a significant gap given the known disparities in both greenspace access and ADRD risk between racialized/ethnic groups and between developed versus developing countries. In this rapid literature review, we (1) describe the diversity of published greenspace-brain health studies with respect to racialized/ethnic groups and geographic regions; (2) determine the extent to which published studies have investigated racialized/ethnic group differences in associations; and (3) review methodological issues surrounding studies of racialized/ethnic group disparities in greenspace and brain health associations. Of the 57 papers meeting our inclusion criteria as of 4 March 2022, 21% (n = 12) explicitly identified and included individuals who were Black, Hispanic/Latinx, and/or Asian. Twenty-one percent of studies (n = 12) were conducted in developing countries (e.g., China, Dominican Republic, Mexico), and 7% (n = 4) examined racialized/ethnic group differences in greenspace-brain health associations. None of the studies were framed by health disparities, social/structural determinants of health, or related frameworks, despite the known differences in both greenspace availability/quality and dementia risk by racialized/ethnic group and geography. Studies are needed in developing countries and that directly investigate racialized/ethnic group disparities in greenspace-brain health associations to target and promote health equity.

Comparison of static and dynamic exposures to air pollution, noise, and greenness among seniors living in compact-city environments

GPS technology and tracking study designs have gained popularity as a tool to go beyond the limitations of static exposure assessments based on the subject's residence. These dynamic exposure assessment methods offer high potential upside in terms of accuracy but also disadvantages in terms of cost, sample sizes, and types of data generated. Because of that, with our study we aim to understand in which cases researchers need to use GPS-based methods to guarantee the necessary accuracy in exposure assessment. With a sample of 113 seniors living in Barcelona (Spain) we compare their estimated daily exposures to air pollution (PM2.5, PM10, NO2), noise (dB), and greenness (NDVI) using static and dynamic exposure assessment techniques. Results indicate that significant differences between static and dynamic exposure assessments are only present in selected exposures, and would thus suggest that static assessments using the place of residence would provide accurate-enough values across a number of exposures in the case of seniors. Our models for Barcelona's seniors suggest that dynamic exposure would only be required in the case of exposure to smaller particulate matter (PM2.5) and exposure to noise levels. The study signals to the need to consider both the mobility patterns and the built environment context when deciding between static or dynamic measures of exposure assessment.

Neighborhood social organization exposures and racial/ethnic disparities in hypertension risk in Los Angeles

Despite a growing evidence base documenting associations between neighborhood characteristics and the risk of developing high blood pressure, little work has established the role played by neighborhood social organization exposures in racial/ethnic disparities in hypertension risk. There is also ambiguity around prior estimates of neighborhood effects on hypertension prevalence, given the lack of attention paid to individuals' exposures to both residential and nonresidential spaces. This study contributes to the neighborhoods and hypertension literature by using novel longitudinal data from the Los Angeles Family and Neighborhood Survey to construct exposure-weighted measures of neighborhood social organization characteristics-organizational participation and collective efficacy-and examine their associations with hypertension risk, as well as their relative contributions to racial/ethnic differences in hypertension. We also assess whether the hypertension effects of neighborhood social organization vary across our sample of Black, Latino, and White adults. Results from random effects logistic regression models indicate that adults living in neighborhoods where people are highly active in informal and formal organizations have a lower probability of being hypertensive. This protective effect of exposure to neighborhood organizational participation is also significantly stronger for Black adults than Latino and White adults, such that, at high levels of neighborhood organizational participation, the observed Black-White and Black-Latino hypertension differences are substantially reduced to nonsignificance. Nonlinear decomposition results also indicate that almost one-fifth of the Black-White hypertension gap can be explained by differential exposures to neighborhood social organization.

Neighborhood characteristics and opioid use disorder among older Medicare beneficiaries: An examination of the role of the COVID-19 pandemic

This study investigates how the associations between residential characteristics and the risk of opioid user disorder (OUD) among older Medicare beneficiaries (age≥65) are altered by the COVID-19 pandemic. Applying matching techniques and multilevel modeling to the Medicare fee-for-service claims data, this study finds that county-level social isolation, concentrated disadvantage, and residential stability are significantly associated with OUD among older adults (N = 1,080,350) and that those living in counties with low levels of social isolation and residential stability experienced a heightened risk of OUD during the pandemic. The results suggest that the COVID-19 pandemic has aggravated the impacts of residential features on OUD.

Geographic Isolation, Compelled Mobility, and Everyday Exposure to Neighborhood Racial Composition Among Urban Youth. AJS; AMERICAN JOURNAL OF SOCIOLOGY 2022;128:914-961. [PMID: 38213504 PMCID: PMC10783811 DOI: 10.1086/721666]

Foundational urban social theories view heterogeneity of exposure to spatial and social contexts as essential aspects of the urban experience. In contrast, contemporary neighborhood research emphasizes the isolation of city dwellers - particularly residents of racially segregated neighborhoods. Using geospatial data on a sample of youth from the 2014-16 Columbus, OH-based Adolescent Health and Development in Context study, we explore the extent to which the neighborhood locations of everyday activities vary with respect to residential racial composition. In the context of segregated US metro areas, the geographic isolation approach expects home census tract racial composition to powerfully shape the racial composition of activity location neighborhoods. In this view, Black youth residing in high proportion Black neighborhoods are expected to spend the vast majority of their time exposed to similarly Black-concentrated neighborhoods. Consistent with an alternative compelled mobility approach, we find that Black youth residing in high proportion Black neighborhoods exhibit among the highest levels of heterogeneity in the racial composition of neighborhoods encountered. Moreover, Black youth residing in high proportion Black neighborhoods are expected to spend 39% of their non-home time (roughly 2.5 hours a day) in low proportion Black neighborhoods compared to 23% (1.5 hours) in high proportion Black neighborhoods. Exposures to low proportion Black neighborhoods among these youth are largely driven by organizationally-based resource seeking. These findings call into question the assumption that residence in Black segregated neighborhoods leads to homogeneously Black segregated neighborhood exposures and encourage theoretical development and data collection strategies that acknowledge the potential for significant heterogeneity in the everyday neighborhood experiences of urban youth.

Investigating how researcher-defined buffers and self-drawn neighbourhoods capture adolescent availability to physical activity facilities and greenspaces: An exploratory study

BACKGROUND

Modifying the environment is considered an effective population-level approach for increasing healthy behaviours, but associations remain ambiguous. This exploratory study aims to compare researcher-defined buffers and self-drawn neighbourhoods (SDN) to objectively measured availability of physical activity (PA) facilities and greenspaces in adolescents.

METHODS

Seven consecutive days of GPS data were collected in an adolescent sample of 14-18 year olds (n = 69). Using Points of Interest and greenspace data, availability of PA opportunities within activity spaces were determined. We compared 30 different definitions of researcher-defined neighbourhoods and SDNs to objectively measured availability.

RESULTS

Findings showed low agreement for all researcher-defined buffers in measuring the availability of PA facilities in activity spaces. However, results were less clear for greenspace. SDNs also demonstrate low agreement for capturing availability to the PA environment.

CONCLUSION

This exploratory study highlights the inadequacy of researcher-defined buffers and SDNs to define availability to environmental features.

Connecting the dots: understanding how human mobility shapes TB epidemics

Tuberculosis (TB) remains a leading infectious cause of death worldwide. Reducing TB infections and TB-related deaths rests ultimately on stopping forward transmission from infectious to susceptible individuals. Critical to this effort is understanding how human host mobility shapes the transmission and dispersal of new or existing strains of Mycobacterium tuberculosis (Mtb). Important questions remain unanswered. What kinds of mobility, over what temporal and spatial scales, facilitate TB transmission? How do human mobility patterns influence the dispersal of novel Mtb strains, including emergent drug-resistant strains? This review summarizes the current state of knowledge on mobility and TB epidemic dynamics, using examples from three topic areas, including inference of genetic and spatial clustering of infections, delineating source-sink dynamics, and mapping the dispersal of novel TB strains, to examine scientific questions and methodological issues within this topic. We also review new data sources for measuring human mobility, including mobile phone-associated movement data, and discuss important limitations on their use in TB epidemiology.

Not built for families: Associations between neighborhood disinvestment and reduced parental cognitive stimulation

Infants learn and develop within an ecological context that includes family, peers, and broader built and social environments. This development relies on proximal processes—reciprocal interactions between infants and the people and environments around them that help them understand their world. Most research examining predictors of proximal processes like parent-child interaction and parenting has focused on elements within the home and family. However, factors like the neighborhood built environment may also exhibit an influence, and may be particularly critical in infancy, as socioeconomic disparities in cognition and language emerge early in life. Moreover, influence from the built environment could independently exacerbate these disparities, as research indicates that neighborhood impacts may be especially relevant for families living in neighborhoods that have experienced disinvestment and therefore have been under-resourced. The current study examines these questions by determining the association of neighborhood vacancy rate and observed physical disorder—indicators of poverty, residential stability, and long-term structural discrimination—with parental cognitive stimulation among predominantly Black/African-American families in Flint, Michigan. Flint is particularly salient for this study because vacancy rates and disinvestment vary widely across the city, driven by its long-time status as a city struggling economically. Regression analyses controlling for caregiver education, mental health, and social support indicated that vacancy rate and physical disorder negatively predicted parental cognitive stimulation. Moreover, there were significant interactions between the built environment and social support, indicating that, particularly for parent-child shared reading, vacancy rate and physical disorder predicted reduced shared reading only when parents had limited social support. These results have important implications for public policy around vacant property demolition and neighborhood reinvestment programs, as they indicate that the neighborhood built environment is associated with parenting behaviors that have important impacts on infants’ learning and development.

Mapping the Way to Good Health: The Interdisciplinary Challenges of Geographers in Medical Research

Geography has an important role to play in shaping the direction of medical research. In particular, its tools and theory provide essential understanding to the impacts of place on health behaviors and outcomes. Understanding some of its evolution-particularly into the subfield of medical geography-is therefore useful both for geographers and medical researchers. In this paper, we present some of the debates that geographers have grappled with, the growth of GIS (particularly in the context of medical research), some important methodological considerations that geographers help center, and some recommendations for future work at this nexus. Throughout, we speak from the perspective of geographers who have worked nearly exclusively in the health sciences since obtaining our PhDs.

Connected in health: Place-to-place commuting networks and COVID-19 spillovers

Biweekly county COVID-19 data were linked with Longitudinal Employer-Household Dynamics data to analyze population risk exposures enabled by pre-pandemic, country-wide commuter networks. Results from fixed-effects, spatial, and computational statistical approaches showed that commuting network exposure to COVID-19 predicted an area's COVID-19 cases and deaths, indicating spillovers. Commuting spillovers between counties were independent from geographic contiguity, pandemic-time mobility, or social media ties. Results suggest that commuting connections form enduring social linkages with effects on health that can withstand mobility disruptions. Findings contribute to a growing relational view of health and place, with implications for neighborhood effects research and place-based policies.

Socially Connected Neighborhoods and the Spread of Sexually Transmitted Infections

Sexually transmitted infections (STIs) in the United States have been increasing at record levels and exhibit unequal spatial patterning across urban populations and neighborhoods. Research on the effects of residential and nearby neighborhoods on STI proliferation has largely ignored the role of socially connected contexts, even though neighborhoods are routinely linked by individuals' movements across space for work and other social activities. We showcase how commuting and public transit networks contribute to the social spillover of STIs in Chicago. Examining data on all employee-employer location links recorded yearly by the Census Bureau for more than a decade, we assess network spillover effects of local community STI rates on interconnected communities. Spatial and network autoregressive models show that exposure to STIs in geographically proximate and socially proximate communities contributes to increases in local STI levels, even net of socioeconomic and demographic factors and prior STIs. These findings suggest that geographically proximate and socially connected communities influence one another's infection rates through social spillover effects.

Time-activity and daily mobility patterns during pregnancy and early postpartum - evidence from the MADRES cohort

INTRODUCTION

Pregnant women's daily time-activity and mobility patterns determine their environmental exposures and subsequently related health effects. Most studies ignore these and assess pregnancy exposures using static residential measures.

METHODS

We conducted 4-day continuous geo-location monitoring in 62 pregnant Hispanic women, during pregnancy and early post-partum then derived trips by mode and stays, classified by context (indoor/outdoor, type). Generalized mixed-effect models were used to examine whether these patterns changed over time.

RESULTS

Women spent on average 17.3 h/day at home. Commercial and service locations were the most popular non-home destinations, while parks and open spaces were seldom visited. Women made 3.5 daily trips (63.7 min/day and approximately 25% were pedestrian-based). Women were less likely to visit commercial and services locations and make vehicle-based trips postpartum compared to the 3^rd trimester.

CONCLUSION

Our findings suggest time-activity patterns vary across pregnancy and postpartum, thus assessing exposures at stationary locations might introduce measurement error.

Patient-reported outcome measures can advance population health, but is access to instruments and use equitable?

Patient reported outcome measures (PROM) can engage patients and clinicians to improve health outcomes. Their population health impact may be limited by systematic barriers inhibiting access to completion. In this analysis we evaluated the association between individual parent/child characteristics and clinic factors with parental completion of a locally developed PROM, the Early Healthy Lifestyles (EHL) questionnaire. Participants included parent-child dyads who presented at 14 pediatric clinics for regularly scheduled well-child visits (WCV) prior to age 26 months. EHL items include feeding practices, diet, play time, screen exposure, and sleep. Completion was categorized at patient- (i.e., parent-child dyad) and clinic-levels. Parents completed the 15-item EHL in the patient portal before arrival or in the clinic; ninety-three percent of EHL questionnaires were completed in the clinic vs. 7% in the patient portal. High-completers completed EHL for half of WCVs; low-completers completed at least once; and non-completers never completed. Clinics were classified by EHL adoption level (% high completion): High-adoption: >50%; Moderate-adoption: 10%-50%; and Low-adoption: <10%. Individual-level factors had negligible impact on EHL completion within moderate/low EHL adoption sites; high-adoption sites were used to evaluate infant and maternal factors in association with EHL completion using hierarchical logistic regression. Noncompletion of EHL was significantly associated (p < 0.05) with infant use of public insurance (OR = 1.92 [1.42, 2.59]), >1 clinic site for WCV (OR = 1.83 [1.34, 2.50]), non-White birth mother (OR = 1.78 [1.28, 2.47]), and body weight <2,500 grams or gestational age <34 weeks (OR = 1.74 [1.05, 2.90]). The number of WCVs, a proxy for clinic size, was evaluated but was not associated with completion. Findings indicate potential disparities between populations exposed to, completing, and benefitting from these tools.

Adolescent Development in Context: A Decade Review of Neighborhood and Activity Space Research

Over the last decade, two lines of inquiry have emerged from earlier investigations of adolescent neighborhood effects. First, researchers began incorporating space-time geography to study adolescent development within activity spaces or routine activity locations and settings. Second, cultural-developmental researchers implicated neighborhood settings in cultural development, to capture neighborhood effects on competencies and processes that are salient or normative for minoritized youth. We review the decade's studies on adolescent externalizing, internalizing, academic achievement, health, and cultural development within neighborhoods and activity spaces. We offer recommendations supporting decompartmentalization of cultural-developmental and activity space scholarship to advance the science of adolescent development in context.

Activity Locations, Residential Segregation, and the Significance of Residential Neighborhood Boundary Perceptions

The inadequacies of residential census geography in capturing urban residents' routine exposures have motivated efforts to more directly measure residents' activity spaces. In turn, insights regarding urban activity patterns have been used to motivate alternative residential neighborhood measurement strategies incorporating dimensions of activity space in the form of egocentric neighborhoods-measurement approaches that place individuals at the center of their own residential neighborhood units. Unexamined, however, is the extent to which the boundaries of residents' own self-defined residential neighborhoods compare with census-based and egocentric neighborhood measurement approaches in aligning with residents' routine activity locations. We first assess this question, examining whether the boundaries of residents' self-defined residential neighborhoods are in closer proximity to the coordinates of a range of activity location types than are the boundaries of their census and egocentric residential neighborhood measurement approaches. We find little evidence that egocentric or, crucially, self-defined residential neighborhoods better align with activity locations, suggesting a division in residents' activity locations and conceptions of their residential neighborhoods. We then examine opposing hypotheses about how self-defined residential neighborhoods and census tracts compare in socioeconomic and racial composition. Overall, our findings suggest that residents bound less segregated neighborhoods than those produced by census geography, but self-defined residential neighborhoods still reflect a preference toward homophily when considering areas beyond the immediate environment of their residence. These findings underscore the significance of individuals' conceptions of residential neighborhoods to understanding and measuring urban social processes such as residential segregation and social disorganization.

Sociodemographic inequities in tobacco retailer density: Do neighboring places matter?

We apply a spatial perspective to measure the extent to which the 2018 U.S. racial, ethnic, and socioeconomic composition of census tracts were each associated with tobacco retailer density within a tract and in its neighboring tracts (n = 71,409). A 10-percentage point increase in the Black population was associated with 0.07 (p < 0.05) more retailers per square mile within a focal tract and 0.35 (p < 0.001) more retailers per square mile in its neighbors on average. A greater percent of Hispanic/Latino residents was associated with more retailers per square mile, both within a focal tract (b = 0.95, p < 0.001) and in its neighbors 0.39 (p < 0.001). Inverse associations were observed for percent white. We also observed inequities by socioeconomic status. The overall magnitude of inequities may be underestimated if the spatial dependence between focal tracts and their neighbors are not taken into consideration. Policymakers should prioritize interconnected geographic areas experiencing high racialized and socioeconomic segregation when designing and implementing policies to reduce retail tobacco product availability.

Modeling the Social and Spatial Proximity of Crime: Domestic and Sexual Violence Across Neighborhoods

OBJECTIVES

Our goal is to understand the social dynamics affecting domestic and sexual violence in urban areas by investigating the role of connections between area nodes, or communities. We use innovative methods adapted from spatial statistics to investigate the importance of social proximity measured based on connectedness pathways between area nodes. In doing so, we seek to extend the standard treatment in the neighborhoods and crime literature of areas like census blocks as independent analytical units or as interdependent primarily due to geographic proximity.

METHODS

In this paper, we develop techniques to incorporate two types of proximity, geographic proximity and commuting proximity in spatial generalized linear mixed models (SGLMM) in order to estimate domestic and sexual violence in Detroit, Michigan and Arlington County, Virginia. Analyses are based on three types of CAR models (the Besag, York, and Mollié (BYM), Leroux, and the sparse SGLMM models) and two types of SAR models (the spatial lag and spatial error models) to examine how results vary with different model assumptions. We use data from local and federal sources such as the Police Data Initiative and American Community Survey.

RESULTS

Analyses show that incorporating information on commuting ties, a non-spatially bounded form of social proximity, to spatial models contributes to better deviance information criteria (DIC) scores (a metric which explicitly accounts for model fit and complexity) in Arlington for sexual and domestic crime as well as overall crime. In Detroit, the fit is improved only for overall crime. The distinctions in model fit are less pronounced when using cross-validated mean absolute error (MAE) as a comparison criteria.

CONCLUSION

Overall, the results indicate variations across crime type, urban contexts, and modeling approaches. Nonetheless, in important contexts, commuting ties among neighborhoods are observed to greatly improve our understanding of urban crime. If such ties contribute to the transfer of norms, social support, resources, and behaviors between places, they may then transfer also the effects of crime prevention efforts.

Participatory geographic mapping and activity space diaries: innovative data collection methods for understanding environmental risk exposures among female sex workers in a low-to middle-income country

Background

A common approach for measuring place-based exposure is to use geographically-defined administrative boundaries and to link neighborhood characteristics at this level. This approach, however, may not be feasible in low-to middle-income countries where neighborhood-level data are limited or unavailable, and administrative boundaries are often unstandardized and not proportional to population size. Furthermore, such traditional approaches may not be appropriate for marginalized populations whose environments can be more difficult to study. In this paper, we describe two innovative and feasible methods to generate geospatial data to characterize and assess the role of risk environments on drug use among female sex workers living with HIV in the Dominican Republic.

Methods

Participatory geographic mapping and daily activity space travel diaries were employed.

Results

The methods presented in this study were feasible to implement, acceptable by study participants, and yielded rich geospatial data to analyze the impact of contextual factors on risk behaviors of female sex workers in a low-to middle-income country.

Conclusion

Participatory geographic mapping and activity space diaries are two alternative methods for collecting geospatial data among hard-to-reach populations in resource constrained settings. Moreover, the methods are interactive and educational, allowing study participants to take an active role in the data collection process and potentially allowing for a deeper understanding of place-based effects on health and behavior.

Change in GPS-assessed walking locations following a cluster-randomized controlled physical activity trial in older adults, results from the MIPARC trial

This study employed novel GPS methods to assess the effect of a multilevel physical activity (PA) intervention on device-measured walking locations in 305 community dwelling older adults, ages 65+ (mean age = 83, 73% women). Retirement communities were randomized to a 1-year PA intervention that encouraged neighborhood walking, or to a healthy aging control condition. Total time and time spent walking in four life-space domains were assessed using GPS and accelerometer devices. The intervention increased the time spent walking as a proportion of total time spent in the Campus, Neighborhood and Beyond Neighborhood domains. Intervention effects on walking location were observed in both genders and across physical and cognitive functioning groups. Results demonstrate that an intervention providing individual, social and environmental support for walking can increase PA in larger life-space domains for a broad spectrum of older adults.

Associations between the built environment and dietary intake, physical activity, and obesity: A scoping review of reviews

There exists a large body of literature examining the association between built environment factors and dietary intake, physical activity, and weight status; however, synthesis of this literature has been limited. To address this gap, we conducted a scoping review of reviews and identified 74 reviews and meta-analyses that investigated the association between built environment factors and dietary intake, physical activity, and/or weight status. Results across reviews were mixed, with heterogeneous effects demonstrated in terms of strength and statistical significance; however, preliminary support was identified for several built environment factors. For example, quality of dietary intake appeared to be associated with the availability of grocery stores, higher levels of physical activity appeared to be most consistently associated with greater walkability, and lower weight status was associated with greater diversity in land-use mix. Overall, reviews reported substantial concern regarding methodological limitations and poor quality of existing studies. Future research should focus on improving study quality (e.g., using longitudinal methods, including natural experiments, and newer mobile sensing technologies) and consensus should be drawn regarding how to define and measure both built environment factors and weight-related outcomes.

Neighborhoods, Activity Spaces, and the Span of Adolescent Exposures

Since the inception of urban sociology, the "neighborhood" has served as the dominant context thought to capture developmentally significant youth experiences beyond the home. Yet no large-scale study has examined patterns of exposure to the most commonly used operationalization of neighborhood - the census tract - among urban youth. Using smartphone GPS data from the Adolescent Health and Development in Context study (N=1405), we estimate the amount of time youth spend in residential neighborhoods and consider explanations for variation in neighborhood exposure. On average, youth (ages 11 to 17) spend 5.7% of their waking time in their neighborhood but not at home, 60% at home, and 34.3% outside their neighborhood. Multilevel negative binomial regression models indicate that residence in economically disadvantaged neighborhoods is associated with less time in neighborhood. Higher levels of local violence and the absence of a neighborhood school the youth is eligible to attend are negatively associated with time in neighborhood and mediate the concentrated disadvantage effect. Fractional multinomial logit models indicate that higher violence is linked with increased time at home while school absence is associated with increased outside-neighborhood time. Theoretical development and empirical research on neighborhood effects should incorporate findings on the extent and nature of neighborhood and broader activity space exposures among urban youth.

Daily activity spaces and drug use among female sex workers living with HIV in the Dominican Republic

The purpose of this study was to explore the daily activity spaces of female sex workers living with HIV in the Dominican Republic and assess the relationship between activity path and location-based risk exposure measures and daily drug use. The study employed a micro-longitudinal observational study design using an innovative 7-day travel diary to capture daily activity routes and a 7-day mobile health (mHealth) daily diary to collect daily substance use behaviors among 51 female sex workers. To estimate between-subject variability, a series of crude and adjusted modified log-Poisson repeated measures regression models with generalized estimating equations, clustering by individual with a compound symmetry working correlation structure were fit to estimate the relative risks and 95% confidence intervals. Controlling for individual level factors, findings showed that female sex workers exposed to a higher number of risk outlets (e.g., liquor stores, bars, hotels, nightclubs, brothels, etc.) within 200 and 100-meters of sex work locations were at an increased risk of daily drug use (RRadj: 1.03, 95%CI: 1.01, 1.05, RRadj: 1.05, 95%CI: 1.01, 1.09). No association was detected between activity path exposure and daily drug use. These findings illustrate the importance of moving beyond static residential neighborhood boundaries for measuring risk exposures and highlight the significant role that daily work environments have on drug harms among a highly stigmatized and vulnerable population.

The multidimensional clustering of health and its ecological risk factors

A diverse set of research has examined the ways in which population-level health and its ecological risk factors are embedded within self-reinforcing structures. Syndemic theory, for example, focuses on the co-occurrence of multiple diseases, whereas the spatial diffusion literature highlights the concentration of poor health among communities sharing geographic boundaries. This study combines these related but disciplinarily-isolated perspectives to examine the clustering of population-level health and its determinants across four dimensions: co-occurrence, spatial, temporal, and social network. Using data on U.S. county-level health outcomes and health factors from the Robert Wood Johnson Foundation's County Health Rankings, this study estimates associations between health outcomes within communities and the co-occurrence of community-level factors theorized to influence ecological health. Not only do health outcomes and their ecological risk factors cluster within counties, but also between geographically adjacent counties and counties connected via migration network pathways. Moreover, the self-reinforcing structures uncovered across the co-occurrence, spatial and network dimensions persist over time, and this clustering has consequences on county health and well-being. Rather than adopting the perspective that either health and its community-level factors should be broadly targeted and detached from local context or communities are different, have unique needs and thus should be treated in isolation, the approach advanced in this study identifies shared vulnerabilities in a way that allows for the development of knowledge networks between communities dealing with similar issues.

Clinical geography: A proposal to embrace space, place and wellbeing through person-centered practice

This essay envisions how geography can operationalize nuanced understandings of space and place to enrich the lives of individuals across the lifespan. We propose a focused integration of geography into person-centered practice: a clinical geography dedicated to working directly with people to promote optimal physical and mental health outcomes and wellbeing. Our proposal integrates spatial modifications to facilitate access and utility, behavioral interventions to maximize effectiveness in using space, and therapeutic engagement to nurture a deeper sense of 'being in place' that enhances wellbeing and quality of life. This focus is timely given societal instability and precariousness resulting from incongruous person-environment situations. In addition to investigating, explaining, and critiquing hazardous and inappropriate conditions, geographers might also directly and more immediately intervene with people who find themselves in such situations.

Human Mobility and Crime: Theoretical Approaches and Novel Data Collection Strategies

This review outlines approaches to explanations of crime that incorporate the concept of human mobility-or the patterns of movement throughout space of individuals or populations in the context of everyday routines-with a focus on novel strategies for the collection of geographically referenced data on mobility patterns. We identify three approaches to understanding mobility-crime linkages: (a) Place and neighborhood approaches characterize local spatial units of analysis of varying size with respect to the intersection in space and time of potential offenders, victims, and guardians; (b) person-centered approaches emphasize the spatial trajectories of individuals and person-place interactions that influence crime risk; and (c) ecological network approaches consider links between persons or collectivities based on shared activity locations, capturing influences of broader systems of interconnection on spatial- and individual-level variation in crime. We review data collection strategies for the measurement of mobility across these approaches, considering both the challenges and promise of mobility-based research for criminology.

Neighborhood Disorder and Distress in Real Time: Evidence from a Smartphone-Based Study of Older Adults

Socioeconomic disadvantage and disorder in the residential neighborhood have been linked to multiple health risks, but less is known about the relevance of other spaces of daily life. This article considers whether disadvantage and disorder in the immediate context-within or outside of the residential neighborhood-is associated with physiological symptoms indicative of stress and strain. We use data from a study of 61 older adults in four New York City neighborhoods. Participants carried smartphones to capture GPS locations and ecological momentary assessments during the study week. We find that instantaneous exposure to disorder is associated with momentary spikes in pain and fatigue. This is not explained by cumulative exposure to disorder or concurrent stress or fear. Rather, disordered spaces may be physically and cognitively taxing for older adults in real time. We urge further research on short- and long-term health consequences of activity spaces.

Assessment of spatial mobility among young men who have sex with men within and across high HIV prevalence neighborhoods in New York city: The P18 neighborhood study

The purpose of this study was to examine and quantify spatial mobility among HIV-negative young men who have sex with men (YMSM) within and across high prevalence HIV neighborhoods in New York City (NYC). We completed an analysis with global positioning system (GPS) and survey data to quantify spatial mobility for participants enrolled in the P18 Neighborhood Study (analytic n = 211; 83.4%). Spatial mobility was documented with self-reported survey data and objective GPS data, which was uncorrelated. Nearly one-quarter of participants (26.1%) said that they consider the neighborhood in which they currently live to differ from the neighborhood in which they had sex most frequently. In addition, 62.9% of participants' GPS points were recorded in NYC ZIP Code Tabulation Areas within the highest quartile of HIV prevalence. Future studies of YMSM populations should be conducted to examine how environments beyond the residential neighborhood can influence sexual health, which may guide HIV prevention services.

An activity space approach to understanding how food access is associated with dietary intake and BMI among urban, low-income African American women

Inconclusive evidence for how food environments affect health may result from an emphasis on residential neighborhood-based measures of exposure. We used an activity space approach to examine whether 1) measures of food access and 2) associations with diet and BMI differ between residential and activity space food environments among low-income African American women in Atlanta, Georgia (n = 199). Although residential and activity space environments differed across all dimensions of food access, being located farther away from 'unhealthy' outlets was associated with lower BMI in both environments. Future research should move beyond asking whether residential and activity space environments differ, toward examining if, how, and under what conditions these differences impact the estimation of health effects.

Neighborhood Poverty and Physical Health at Midlife: The Role of Life-Course Exposure

Studies of the effect of neighborhood poverty on health are dominated by research designs that measure neighborhood poverty at a single point in time, ignoring the potential influence of exposure to neighborhood poverty over the life course. Applying latent class analysis to restricted residential history data from the National Longitudinal Survey of Youth, 1979 Cohort, we identify four trajectories of life-course exposure to high-poverty neighborhoods between adolescence and midlife and then examine how these groups differ in their physical health conditions (SF-12 score) and self-rated health at around age 40. Linear and logistic regression analyses show that life-course exposure to high-poverty neighborhoods is a stronger predictor of midlife physical health than are point-in-time measures of neighborhood poverty observed during either adolescence or midlife. Our findings suggest that a life-course approach can enhance our understanding of how neighborhood poverty affects physical health.

Social environment and quality of life among older people with diabetes and multiple chronic illnesses in New Zealand: Intermediary effects of psychosocial support and constraints

Purpose: In older people with diabetes, multimorbidity is highly prevalent and it can lead to poor quality of life. The overall purpose of this study was to examine the association between the social environment, psychosocial support and constraints, and overall quality of life among older people with and without with diabetes and multiple chronic illnesses.Methods: Self-reported data from participants in a cohort study of older New Zealanders was analysed. Responses from 380 older people diagnosed with diabetes and multiple chronic illnesses were compared with 527 older people with no health issues on indicators related to the associations of neighbourhood, health and ageing, using structural equation modelling.Results: The final model suggests that social provision, purpose in life and capabilities mediated between the social environment and quality of life, indicate that older people with positive social environment (i.e., neighbourhood advantage, residential stability) are much less likely to experience depression due to having good social support, meaningful life purpose and opportunities to engage.Conclusions: Perceived neighbourhood advantages, such as positive neighbourhood qualities, social cohesion and housing satisfaction, along with the focus on increasing social support, enhancing purpose in life and supporting one's capability to achieve, may serve as protective factors against depression.IMPLICATIONS FOR REHABILITATIONEnvironmental and personal circumstances can contribute to quality of life among older people with diabetes and multimorbidity.By providing older people with diabetes and multiple chronic illnesses a socially just environment that challenges ageism and other forms of oppression, this could reduce social disparities in health, improve inclusion and access to resources.Social and healthcare professionals are encouraged to design clinical care guidelines and rehabilitation goals from a wholistic and person/client centred approach to support older people with diabetes and multiple chronic illnesses.

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.

Influence of Individual and Contextual Perceptions and of Multiple Neighborhoods on Depression

The risk of depression is related to multiple various determinants. The consideration of multiple neighborhoods daily frequented by individuals has led to increased interest in analyzing socio-territorial inequalities in health. In this context, the main objective of this study was (i) to describe and analyze the spatial distribution of depression and (ii) to investigate the role of the perception of the different frequented spaces in the risk of depression in the overall population and in the population stratified by gender. Data were extracted from the 2010 SIRS (a French acronym for "health, inequalities and social ruptures") cohort survey. In addition to the classic individual characteristics, the participants reported their residential neighborhoods, their workplace neighborhoods and a third one: a daily frequented neighborhood. A new approach was developed to simultaneously consider the three reported neighborhoods to better quantify the level of neighborhood socioeconomic deprivation. Multiple simple and cross-classified multilevel logistic regression models were used to analyze the data. Depression was reported more frequently in low-income (OR = 1.89; CI = [1.07-3.35]) or middle-income (OR = 1.91; CI = [1.09-3.36]) neighborhoods and those with cumulative poverty (OR = 1.64; CI = [1.10-2.45]). In conclusion, a cumulative exposure score, such as the one presented here, may be an appropriate innovative approach to analyzing their effects in the investigation of socio-territorial inequalities in health.

Neighborhood racial, ethnic, and income disparities in accessibility to multiple tobacco retailers: Mecklenburg County, North Carolina, 2015

•Existing studies assess an individual's proximity to a single tobacco retailer.•Measuring proximity to more than one retailer may better capture accessibility.•Disparities in multi-retailer proximity exist by neighborhood race and income.•Policies to address disparities in tobacco retailer exposure are needed.

A statistical framework for measuring the temporal stability of human mobility patterns

Despite the growing popularity of human mobility studies that collect GPS location data, the problem of determining the minimum required length of GPS monitoring has not been addressed in the current statistical literature. In this paper, we tackle this problem by laying out a theoretical framework for assessing the temporal stability of human mobility based on GPS location data. We define several measures of the temporal dynamics of human spatiotemporal trajectories based on the average velocity process, and on activity distributions in a spatial observation window. We demonstrate the use of our methods with data that comprise the GPS locations of 185 individuals over the course of 18 months. Our empirical results suggest that GPS monitoring should be performed over periods of time that are significantly longer than what has been previously suggested. Furthermore, we argue that GPS study designs should take into account demographic groups.

Beyond Activity Space: Detecting Communities in Ecological Networks

Emerging research suggests that the extent to which activity spaces - the collection of an individual's routine activity locations - overlap provides important information about the functioning of a city and its neighborhoods. To study patterns of overlapping activity spaces, we draw on the notion of an ecological network, a type of two-mode network with the two modes being individuals and the geographic locations where individuals perform routine activities. We describe a method for detecting "ecological communities" within these networks based on shared activity locations among individuals. Specifically, we identify latent activity pattern profiles, which, for each community, summarize its members' probability distribution of going to each location, and community assignment vectors, which, for each individual, summarize his/her probability distribution of belonging to each community. Using data from the Adolescent Health and Development in Context (AHDC) Study, we employ latent Dirichlet allocation (LDA) to identify activity pattern profiles and communities. We then explore differences across neighborhoods in the strength, and within-neighborhood consistency of community assignment. We hypothesize that these aspects of the neighborhood structure of ecological community membership capture meaningful dimensions of neighborhood functioning likely to co-vary with economic and racial composition. We discuss the implications of a focus on ecological communities for the conduct of "neighborhood effects" research more broadly.

As Violence Unfolds: A Space-Time Study of Situational Triggers of Violent Victimization among Urban Youth

OBJECTIVES

This study clarifies three important issues regarding situational or opportunity theories of victimization: 1) whether engaging in risk activities triggers violent assault during specific, often fleeting moments, 2) how environmental settings along individuals' daily paths affect their risk of violent assault, and 3) whether situational triggers have differential effects on violent assault during the day versus night.

METHODS

Using an innovative GIS-assisted interview technique, 298 young male violent assault victims in Philadelphia, PA described their activity paths over the course of the day of being assaulted. Case-crossover analyses compared each subject's exposure status at the time of assault with his own statuses earlier in the day (stratified by daytime and nighttime).

RESULTS

Being at an outdoor/public space, conducting unstructured activities, and absence of guardians increase the likelihood of violent victimization at a fine spatial-temporal scale at both daytime and nighttime. Yet, the presence of friends and environmental characteristics have differential effects on violent victimization at daytime versus nighttime. Moreover, individual risk activities appeared to exhibit better predictive performance than did environmental characteristics in our space-time situational analyses.

CONCLUSIONS

This study demonstrates the value of documenting how individuals navigate their daily activity space, and ultimately advances our understanding of youth violence from a real-time, real-life standpoint.

Intergenerational photovoice perspectives of place and health in public housing: Participatory coding, theming, and mapping in/of the "structure struggle"

This paper details an intergenerational photovoice project exploring spatial and perceptual differences of "place" and health among adult and youth public housing residents in a small urban rustbelt city in the Midwestern United States. It specifically highlights the value of fully participatory photovoice processes-participatory narrative-coding and digital web-based photo-mapping-in furthering conceptual and analytical understanding of "place" and health. Results indicate the critical import of accounting for non-residential locations (i.e. activity spaces), and the significance of engaging the generationally- and spatially-specific social and physical landscapes of residents' lived "place" to improve health opportunities within place-based strategies involving public housing.

Feasibility and Validity of Geographically Explicit Ecological Momentary Assessment With Recall-Aided Space-Time Budgets

We employ data from the Adolescent Health and Development in Context Study-a representative sample of urban youth ages 11-17 in and around the Columbus, OH area-to investigate the feasibility and validity of smartphone-based geographically explicit ecological momentary assessment (GEMA). Age, race, household income, familiarity with smartphones, and self-control were associated with missing global positioning systems (GPS) coverage, whereas school day was associated with discordance between percent of time at home based on GPS-only versus recall-aided space-time budget data. Fatigue from protocol compliance increases missing GPS across the week, which results in more discordance. Although some systematic differences were observed, these findings offer evidence that smartphone-based GEMA is a viable method for the collection of activity space data on urban youth.

Critical Hours and Important Environments: Relationships between Afterschool Physical Activity and the Physical Environment Using GPS, GIS and Accelerometers in 10-12-Year-Old Children

Introduction: The objective of this study was to assess relationships between children’s physical environment and afterschool leisure time physical activity (PA) and active transport. Methods: Children aged 10–12 years participated in a 7-day accelerometer and Global Positioning Systems (GPS) protocol. Afterschool leisure time PA and active transport were identified based on location- and speed-algorithms based on accelerometer, GPS and Geospatial Information Systems (GIS) data. We operationalized children’s exposure to the environment by combining home, school and the daily transport environment in individualized daily activity-spaces. Results: In total, 255 children from 20 Dutch primary schools from suburban areas provided valid data. This study showed that greenspaces and smaller distances from the children’s home to school were associated with afterschool leisure time PA and walking. Greater distances between home and school, as well as pedestrian infrastructure were associated with increased cycling. Conclusion: We demonstrated associations between environments and afterschool PA within several behavioral contexts. Future studies are encouraged to target specific behavioral domains and to develop natural experiments based on interactions between several types of the environment, child characteristics and potential socio-cognitive processes.

Neighborhood Experiences of People Over Age 50: Factor Structure and Validity of a Scale

Background and Objectives

Various aspects of the neighborhood environment have been shown to correlate with older adults’ health. Socio-ecological models of health posit that interventions in the living environment can influence population health. Yet, there are no scales to comprehensively measure older people’s experiences of their neighborhoods especially in dense urban contexts. This study analyzes the psychometric properties and factor structure of a holistic measure of Older People’s Neighborhood Experience (OpenX) to understand constituent factors of residential satisfaction and well-being in dense urban contexts.

Research Design and Methods

Participants were 1,011 community-dwelling older adults aged 50 and older in Singapore. Face-to-face interviews were conducted. Questions were drawn to measure physical and social aspects of the neighborhood as well as sociodemographic variables. Exploratory and confirmatory factor analyses were conducted to obtain a shorter version; content validity, internal consistency, and external validity were assessed.

Results

The OpenX has a 4-dimensional structure, explaining 45.5% of the variance of neighborhood experience. They are communal affordance, embeddedness, environment pleasantness, and time outdoors. Good reliability and validity were found, including Cronbach’s alpha of 0.827. The correlation between neighborhood experience and objectively measured proximity to parks and fitness corners approached significance (p = .082).

Discussion and Implications

The 16-item OpenX demonstrated good psychometric properties. With reference to the transdisciplinary neighborhood health framework, it is useful for assessing older adults’ neighborhood environment, identifying neighborhoods for pilot population health interventions, and understanding how the neighborhood environment affects older adults’ health.

Stability of activity space footprint, size, and environmental features over six months

As activity space measures are increasingly used to estimate exposure to environmental determinants of health, little is known about the stability of these measures over time. To test the stability of GPS-derived measures of activity-space footprint, size, and environmental features over time, we compared 14-day measures at baseline and six months later for 35 adults in a large city. Activity-space measures were based on convex hulls and 500 m route buffers, and included the geographic footprint (i.e. location of the activity space), size (i.e., area in square miles; (Cummins, 2007)), and environmental features including supermarket, fast-food restaurant, and parkland density. The proportion of the participants' smaller geographic footprint covered by the larger was, on average, 0.64 (SD 0.17) for the 500 m route buffer and 0.84 (SD 0.18) for the convex hull. Mean percent change in activity space size ranged from 36.3% (mean daily 500 m route buffer) to 221.3% (cumulative convex hull). Mean percent change in the density of environmental features ranged from 28.8 to 66.5%. Forty-one percent to 92.4% of the variance at one timepoint was predicted by environmental features measured within approximately six months. Activity-space size and environmental features were moderately to highly stable over six months, although there was considerable variation in stability between measures. Strategies for addressing measurement error in studies of activity space-health associations are discussed.

Finite mixture models in neighbourhoods-to-health research: A systematic review

A systematic review was conducted, following PRISMA guidelines, to examine the application of finite mixture models (FMMs) in the study of neighbourhoods and health. Two reviewers screened 814-studies identified through database searches and citation tracking. Data were extracted from 19-studies that met the inclusion criteria, and a risk of bias analysis undertaken. Data were synthesised narratively, with a focus on methodological issues idiosyncratic to FMMs. Motivated by a desire to account for neighbourhood heterogeneity, studies sought to identify meaningful neighbourhood-level typologies that explained the distributional nature of health outcomes. Neighbourhood-centred applications of FMMs were promising but there remains scope for advancement. Research-based recommendations are outlined to strengthen prospective neighbourhood-centred studies applying FMMs.