The association between environmental greenness and the risk of food allergy: A population-based study in Melbourne, Australia.

BACKGROUND: While exposure to environmental greenness in childhood has shown mixed associations with the development of allergic disease, the relationship with food allergy has not been explored. We investigated the association between exposure to environmental greenness and challenge-confirmed food allergy in a large population-based cohort. METHODS: The HealthNuts study recruited 5276 12-month-old infants in Melbourne, Australia, who underwent skin prick testing to peanut, egg, and sesame; infants with a detectable wheal underwent food challenges to determine food allergy status. Environmental greenness was estimated using the normalized difference vegetation index (NDVI) for five buffer zones around the infant's home address: at the home, 100 m, 500 m, 800 m, and 1600 m radial distances. Environmental greenness was categorized into 3 tertiles and mixed effects logistic regression models quantified the association between greenness and the risk of food allergy, adjusting for confounding and accounting for clustering at the neighborhood level. RESULTS: NDVI data were available for n = 5097. For most buffer zones, medium and high greenness, compared to low greenness, was associated with an increased risk of peanut allergy (eg, 100 m tertile 2 aOR 1.89 95% CI 1.22-2.95, tertile 3 aOR 1.78 95% CI 1.13-2.82). For egg allergy, the effect sizes were smaller (100 m tertile 2 aOR 1.52 95% CI 1.16-1.97, tertile 3 aOR 1.38 95% CI 1.05-1.82). Socioeconomic status (SES) modified the association between greenness and peanut allergy, but not egg allergy; associations were apparent in the low SES group but not in the high SES group (p for interaction 0.08 at 100 m). Air pollution (PM2.5) also modified the associations between environmental greenness and food allergy, with associations present in high air pollution areas but not low (p for interaction at 100 m 0.05 for peanut and 0.06 for egg allergy.) CONCLUSION: Increased exposure to environmental greenness in the first year of life was associated with an increased risk of food allergy. Increased greenness may correlate with higher pollen levels which may trigger innate immune responses skewing the immune system to the Th2-dependent allergic phenotype; additionally, some pollen and food allergens are cross-reactive. Given the mixed data on greenness and other allergies, the relationship appears complex and may also be influenced by confounding variables outside those that were measured in this study.

Outdoor public recreation spaces and social connectedness among adolescents.

BACKGROUND: Outdoor public recreation spaces are important settings for leisure and physical activity. Adolescents' use of these spaces may contribute to social connectedness via social interaction with peers and the community in these settings. However, research on this topic is limited. This exploratory study examined associations of frequency of visitation and physical activity in outdoor public recreation spaces with social connectedness among adolescents in Melbourne, Australia. METHODS: Adolescents self-reported their frequency of visitation to parks, trails, beach/lake, and sports facilities; frequency of physical activity in a park, local street or path, and their street; and social connectedness. Separate analyses were conducted for visitation (n = 349, 15.4 ± 1.6 years, 58% female) and physical activity (n = 441, 15.4 ± 1.6 years, 59% female) using multilevel linear regression models. RESULTS: No significant associations were observed for frequency of visitation to a park (B = 0.86, 95% CI = - 0.26, 1.99), trails (B = 0.41, 95% CI = - 0.61, 1.44), beach/lake (B = - 0.44, 95% CI = - 1.46, 0.57), or sports facilities (B = 0.64, 95% CI = - 0.43, 1.70), nor for frequency of physical activity in their street (B = - 0.07, 95% CI = - 0.46, 0.31), local street/path (B = - 0.05, 95% CI = - 0.43, 0.33) or in a park (B = 0.23, 95% CI = - 0.14, 0.60) with adolescents' social connectedness. CONCLUSIONS: The findings did not support the hypothesis that visiting and being active in outdoor public recreation spaces are associated with adolescents' social connectedness. Future research should consider the duration and context of outdoor public recreation space use (e.g., sports, socialising, relaxing alone) and whether different types and/or a combination of public spaces are more/less conducive to social connectedness.

Neighbourhood walkability and physical activity: moderating role of a physical activity intervention in overweight and obese older adults with metabolic syndrome.

BACKGROUND: While urban built environments might promote active ageing, an infrequently studied question is how the neighbourhood walkability modulates physical activity changes during a physical activity intervention programme in older adults. We assessed the influence of objectively assessed neighbourhood walkability on the change in physical activity during the intervention programme used in the ongoing PREvención con DIeta MEDiterránea (PREDIMED)-Plus trial. METHOD: The present study involved 228 PREDIMED-Plus senior participants aged between 55 and 75, recruited in Palma de Mallorca (Spain). Overweight/obese older adults with metabolic syndrome were randomised to an intensive weight-loss lifestyle intervention or a control group. A walkability index (residential density, land use mix, intersections density) was calculated using geographic information systems (1 km sausage-network buffer). Physical activity was assessed using accelerometer and a validated questionnaire, at baseline and two follow-up visits (6-months and 1-year later). Generalised additive mixed models were fitted to estimate the association between the neighbourhood walkability index and changes in physical activity during follow-up. RESULTS: Higher neighbourhood walkability (1 z-score increment) was associated with moderate-to-vigorous accelerometer assessed physical activity duration, (ß = 3.44; 95% CI = 0.52; 6.36 min/day). When analyses were stratified by intervention arm, the association was only observed in the intervention group (ß = 6.357; 95% CI = 2.07;10.64 min/day) (P for interaction = 0.055). CONCLUSIONS: The results indicate that the walkability of the neighbourhood could support a physical activity intervention, helping to maintain or increase older adults' physical activity.

Backyard benefits? A cross-sectional study of yard size and greenness and children's physical activity and outdoor play.

BACKGROUND: The home environment is the most important location in young children's lives, yet few studies have examined the relationship between the outdoor home environment and child physical activity levels, and even fewer have used objectively measured exposures and outcomes. This study examined relationships between objectively assessed home yard size and greenness, and child physical activity and outdoor play. METHODS: Data were drawn from the HealthNuts study, a longitudinal study of 5276 children in Melbourne, Australia. We used cross-sectional data from a sample at Wave 3 (2013-2016) when participants were aged 6 years (n = 1648). A sub-sample of 391 children had valid accelerometer data collected from Tri-axial GENEActive accelerometers worn on their non-dominant wrist for 8 consecutive days. Yard area and greenness were calculated using geographic information systems. Objective outcome measures were minutes/day in sedentary, light, and moderate-vigorous physical activity (weekday and weekend separately). Parent-reported outcome measures were minutes/day playing outdoors (weekend and weekday combined). Multi-level regression models (adjusted for child's sex, mother's age at the birth of child, neighbourhood socioeconomic index, maternal education, and maternal ethnicity) estimated effects of yard size and greenness on physical activity. RESULTS: Data were available on outdoor play for 1648 children and usable accelerometer data for 391. Associations between yard size/greenness and components of physical activity were minimal. For example, during weekdays, yard size was not associated with daily minutes in sedentary behaviour (ß: 2.4, 95% CI: - 6.2, 11.0), light physical activity (ß: 1.4, 95% CI: - 5.7, 8.5) or MVPA (ß: -2.4, 95% CI: - 6.5, 1.7), with similar patterns at weekends. There was no relationship between median annual yard greenness and physical activity or play. CONCLUSION: In our study of young children residing in higher socio-economic areas of Melbourne yard characteristics did not appear to have a major impact on children's physical activity. Larger studies with greater variation in yard characteristics and identification of activity location are needed to better understand the importance of home outdoor spaces and guide sustainable city planning.

Reduction in Late-Night Violence following the Introduction of National New Zealand Trading Hour Restrictions.

BACKGROUND: This study aimed to assess the early impact of national alcohol trading hour restrictions on nighttime violence in New Zealand. The new national maximum trading hour restrictions prohibited 24-hour trading by reducing hours to between 8 am and 4 am for on-premises and between 7 am and 11 pm for take-away outlets. METHODS: A telephone survey of alcohol outlets was undertaken to determine actual trading hours before the law change. Interrupted time-series analysis modeled weekly nighttime police calls for service for assault (i.e., between 9 pm and 6 am) and late-night police calls for service for assault (i.e., between 4 am and 6 am) from 2005 to 2015. Daytime police calls for service for assaults were used as the comparison group. Abrupt permanent changes and gradual permanent changes were assessed. RESULTS: The survey found that only 1% of alcohol shops, 9% of supermarkets, and 6% of bars/nightclubs were affected by the hour restrictions because they did not trade as long as their licensed hours permitted in the first place. The time-series analysis found no effect of the national trading hour restrictions on nighttime police calls for service for assaults. However, a significant gradual permanent decrease of 12.4% was found for late-night assaults between 4 am and 6 am (i.e., those likely related to the on-premises hour restriction). This equated to a weekly average decrease of 4.3 police calls for service for assaults between 4 am and 6 am following the law change. CONCLUSIONS: The national trading hour restrictions for on-premises and take-away outlets affected only a small proportion of premises, and no change in the overall level of nighttime violence was found following the restrictions. Late-night assaults likely related to on-premises, however, did reduce showing the likely effectiveness of trading hour restrictions even when the impact of the law change on the ground was minimal.

Built environment and physical activity among adolescents: the moderating effects of neighborhood safety and social support.

BACKGROUND: Increasing emphasis has been placed on improving physical activity levels through multilevel interventions. This study aims to examine moderating effects of neighborhood safety (crime and traffic) and social support (from parent and sibling/peer) for physical activity in the relationship between the built environment and moderate-to-vigorous physical activity (MVPA) outside school hours among adolescents in Melbourne. METHODS: Data were from the NEighbourhood Activity in Youth study conducted among adolescents in Melbourne, Australia (n = 358, 15.3 (SD = 1.5) years). MVPA outside school hours was assessed by accelerometer. Built environment features within 1 km and 2 km residential buffers including recreation facilities, park area, and walkability and its components were assessed using Geographic Information Systems. Neighborhood safety, social support for physical activity and sociodemographic information were self-reported by adolescents. Multilevel linear regression models were used to estimate associations. RESULTS: Support for physical activity from sibling/peer positively moderated the relationship between recreation facilities (1 km), residential density (2 km) and MVPA. Recreation facility (count within 2 km), walkability (1 km and 2 km) and residential density (1 km) had significant positive associations with MVPA outside school hours. CONCLUSION: The built environment appeared to have stronger facilitating effects on MVPA among adolescents who had favourable support for physical activity from their sibling or peer. Multilevel interventions that target the built environment and social factors are needed to promote MVPA outside school hours among adolescents.

Neighborhood walkability and 12-year changes in cardio-metabolic risk: the mediating role of physical activity.

BACKGROUND: Living in walkable neighborhoods may provide long-term cardio-metabolic health benefits to residents. Little empirical research has examined the behavioral mechanisms in this relationship. In this longitudinal study, we examined the potential mediating role of physical activity (baseline and 12-year change) in the relationships of neighborhood walkability with 12-year changes in cardio-metabolic risk markers. METHODS: The Australian Diabetes, Obesity and Lifestyle study collected data from adults, initially aged 25+ years, in 1999-2000, 2004-05, and 2011-12. We used 12-year follow-up data from 2023 participants who did not change their address during the study period. Outcomes were 12-year changes in waist circumference, weight, systolic and diastolic blood pressure, fasting and 2-h postload plasma glucose, high-density lipoprotein cholesterol, and triglycerides. A walkability index was calculated, using dwelling density, intersection density, and destination density, within 1 km street-network buffers around participants' homes. Spatial data for calculating these measures were sourced around the second follow-up period. Physical activity was assessed by self-reported time spent in moderate-to-vigorous physical activity (including walking). Multilevel models, adjusting for potential confounders, were used to examine the total and indirect relationships. The joint-significance test was used to assess mediation. RESULTS: There was evidence for relationships of higher walkability with smaller increases in weight (P = 0.020), systolic blood pressure (P < 0.001), and high-density lipoprotein cholesterol (P = 0.002); and, for relationships of higher walkability with higher baseline physical activity (P = 0.020), which, in turn, related to smaller increases in waist circumference (P = 0.006), weight (P = 0.020), and a greater increase in high-density lipoprotein cholesterol (P = 0.005). There was no evidence for a relationship of a higher walkability with a change in physical activity during the study period (P = 0.590). CONCLUSIONS: Our mediation analysis has shown that the protective effects of walkable neighborhoods against obesity risk may be in part attributable to higher baseline physical activity levels. However, there was no evidence of mediation by increases in physical activity during the study period. Further research is needed to understand other behavioral pathways between walkability and cardio-metabolic health, and to investigate any effects of changes in walkability.

Evidence for the 'safety in density' effect for cyclists: validation of agent-based modelling results.

The safety in numbers (SiN) effect for cyclists is widely observed but remains poorly understood. Although most studies investigating the SiN phenomenon have focused on behavioural adaptation to 'numbers' of cyclists in the road network, previous work in simulated environments has suggested SiN may instead be driven by increases in local cyclist spatial density, which prevents drivers from attempting to move through groups of oncoming cyclists. This study therefore set out to validate the results of prior simulation studies in a real-world environment. Time-gap analysis of cyclists passing through an intersection was conducted using 5 hours of video observation of a single intersection in the city of Melbourne, Australia, where motorists were required to 'yield' to oncoming cyclists. Results demonstrated that potential collisions between motor vehicles and cyclists reduced with increasing cyclists per minute passing through the intersection. These results successfully validate those observed under simulated conditions, supporting evidence of a proposed causal mechanism related to safety in density rather than SiN, per se. Implications of these results for transportation planners, cyclists and transportation safety researchers are discussed, suggesting that increased cyclist safety could be achieved through directing cyclists towards focused, strategic corridors rather than dispersed across a network.

Ecological correlates of activity-related behavior typologies among adolescents.

BACKGROUND: Adolescents engage in various combinations (typologies) of physical activity and sedentary behaviors, which impact their health and wellbeing in different ways. As such, there is a need to understand the factors that may inhibit or facilitate engagement in combinations of activity-related behaviors to help inform effective intervention strategies targeting those most in need. The aim of this study was to identify ecological correlates of adolescent physical activity and sedentary behavior typologies. METHODS: Cross-sectional study of 473 adolescents (15.0 ± 1.6 years, 41.4% boys) from 18 secondary schools in Melbourne, Australia. Intrapersonal, interpersonal and neighborhood-physical environmental factors were assessed via self-report surveys and Geographic Information Systems. Multinomial logistic regression models determined the relative risk ratio of membership of three homogenous activity-related behavior typologies based on the potential correlates. RESULTS: Higher levels of self-efficacy for physical activity, parental screen-time restriction rules, parental support for physical activity, sibling screen-time co-participation and perceptions of neighborhood pedestrian/traffic safety were associated with greater likelihood of adolescents being in the typology defined as highly active and low sedentary compared to the physically inactive, highly sedentary typology. Higher frequency of co-participation in screen-time with friends was associated with greater likelihood of adolescents being in the typology defined as moderately active, high screen-time compared to physically inactive, highly sedentary. CONCLUSIONS: A range of intrapersonal, interpersonal and environmental correlates appear to play a role in adolescent activity-related typology membership. The findings may inform public health interventions targeting unique adolescent subgroups most at risk of poor health outcomes based on their engagement in combinations of activity-related behaviors.

Enabling participation for disabled young people: study protocol.

BACKGROUND: Participation in community life is vital for health and wellbeing, promoting a sense of belonging, networks of social support and opportunities for physical activity. Disabled young people have lower levels of mobility and participation in recreational activities (physical, social and cultural), education and employment, than their peers without disabilities. This has implications for their health and wellbeing and life course opportunities. Previous research on the participation levels of disabled young people has primarily relied on parent/caregiver reports and been oriented to home and school environments. This study investigates how physical and social environmental factors cohere to support or restrict the everyday mobility and participation of disabled young people. METHODS/DESIGN: The study is located in Auckland, Aotearoa/New Zealand (NZ). Participants comprise 35 young people aged 12-25 years with mobility, vision or hearing impairments. A mixed-methods research design combines objective (global positioning systems, accelerometers, geographical information systems) and self-report measures (travel diaries, and questionnaires) to assess young people's mobility and levels of participation in leisure/educational and employment activities with in-depth interviews exploring their everyday experiences of inclusion/exclusion, and factors enabling or constraining community participation. Parents/caregivers and disability sector key informant viewpoints on the community participation of disabled young people have also been gathered through in-depth interviews. Follow-up workshops with young people and parents/caregivers will identify pathways to increase participation and challenge current disabling practices. DISCUSSION: This study looks beyond barriers in the physical environment to the interplay of personal, social and physical factors that enable or constrain the community participation of disabled young people. In keeping with the study's overarching goal of increasing opportunities for effective community participation and full citizenship of disabled young people, research methods were applied flexibily - negotiated and adapted to maximise each young person's participation in light of their abilities and preferences.

Comparing private and public transport access to diabetic health services across inner, middle, and outer suburbs of Melbourne, Australia.

BACKGROUND: Melbourne, Australia is experiencing rapid population growth, with much of this occurring in metropolitan outer suburban areas, also known as urban growth areas. Currently little is known about differences in travel times when using private and public transport to access primary and secondary services across Melbourne's urban growth areas. Plan Melbourne Refresh, a recent strategic land use document has called for a 20 min city, which is where essential services including primary health care, can be accessed within a 20 min journey. Type 2 diabetes mellitus (T2DM) is a major chronic condition in Australia, with some of Melbourne's growth areas having some of the highest prevalence across Australia. This study explores travel times to diabetic health care services for populations residing in inner, middle and outer suburbs of metropolitan Melbourne. METHOD: Geographic information systems (GIS) software were used to map the location of selected diabetic primary and secondary health care service providers across metropolitan inner, middle, outer established, outer urban growth and outer fringe areas of Melbourne. An origin-destination matrix was used to estimate travel distances from point of origin (using a total of approximately 50,000 synthetic residential addresses) to the closest type of each diabetic health care service provider (destinations) across Melbourne. ArcGIS was used to estimate travel times for private transport and public transport; comparisons were made by area. RESULTS: Our study indicated increased travel times to diabetic health services for people living in Melbourne's outer growth and outer fringe areas compared with the rest of Melbourne (inner, middle and outer established). Compared with those living in inner city areas, the median time spent travelling to diabetic services was between 2.46 and 23.24 min (private motor vehicle) and 12.01 and 43.15 min (public transport) longer for those living in outer suburban areas. Irrespective of travel mode used, results indicate that those living in inner and middle suburbs of Melbourne have shorter travel times to access diabetic health services, compared with those living in outer areas of Melbourne. Private motor vehicle travel times were approximately 4 to 5 times faster than public transport modes to access diabetic health services in all areas. CONCLUSION: Those living in new urban growth communities spend considerably more time travelling to access diabetic health services - particularly specialists - than those living in established areas across Melbourne.

Designing healthy communities: creating evidence on metrics for built environment features associated with walkable neighbourhood activity centres.

BACKGROUND: Evidence-based metrics are needed to inform urban policy to create healthy walkable communities. Most active living research has developed metrics of the environment around residential addresses, ignoring other important walking locations. Therefore, this study examined: metrics for built environment features surrounding local shopping centres, (known in Melbourne, Australia as neighbourhood activity centres (NACs) which are typically anchored by a supermarket); the association between NACs and transport walking; and, policy compliance for supermarket provision. METHODS: In this observational study, cluster analysis was used to categorize 534 NACs in Melbourne, Australia by their built environment features. The NACS were linked to eligible Victorian Integrated Survey of Travel Activity 2009-2010 (VISTA) survey participants (n=19,984). Adjusted multilevel logistic regressions estimated associations between each cluster typology and two outcomes of daily walking: any transport walking; and, any 'neighbourhood' transport walking. Distance between residential dwellings and closest NAC was assessed to evaluate compliance with local planning policy on supermarket locations. RESULTS: Metrics for 19 built environment features were estimated and three NAC clusters associated with walkability were identified. NACs with significantly higher street connectivity (mean:161, SD:20), destination diversity (mean:16, SD:0.4); and net residential density (mean:77, SD:65) were interpreted as being 'highly walkable' when compared with 'low walkable' NACs, which had lower street connectivity (mean:57, SD:15); destination diversity (mean:11, SD:3); and net residential density (mean:10, SD:3). The odds of any daily transport walking was 5.85 times higher (95% CI: 4.22, 8.11), and for any 'neighborhood' transport walking 8.66 (95% CI: 5.89, 12.72) times higher, for residents whose closest NAC was highly walkable compared with those living near low walkable NACs. Only highly walkable NACs met the policy requirement that residents live within 1km of a local supermarket. CONCLUSIONS: Built environment features surrounding NACs must reach certain levels to encourage walking and deliver walkable communities. Research and metrics about the type and quantity of built environment features around both walking trip origins and destinations is needed to inform urban planning policies and urban design guidelines.

Associations of the perceived and objective neighborhood environment with physical activity and sedentary time in New Zealand adolescents.

BACKGROUND: There is accumulating evidence supporting the association between neighborhood built environments and adults' physical activity (PA) and sedentary time (ST); however, few studies have investigated these associations in adolescents. A better understanding of the features of the built environment that encourage PA or ST is therefore of critical importance to promote health and wellbeing in adolescents. The aim of this study was to estimate the associations of GIS-determined and perceived walkability components in individual residential buffer zones with accelerometer-assessed moderate-to-vigorous physical activity (MVPA) and ST in adolescents. METHODS: The Built Environment in Adolescent New Zealanders (BEANZ) study was conducted in two cities (Auckland and Wellington) during the 2013-2014 academic school years. The exposure measures were subjective and objective environmental indices of activity-friendliness using four residential buffers. Road network buffers were calculated around participant's residential addresses using the sausage buffer approach at 250 m, 500 m, 1 km, and 2 km scales. A 25 m radius was used for the buffers. Data were analysed using Generalized Additive Mixed Models in R. RESULTS: Data were analysed from 524 participants (15.78 ± 1.62 years; 45% male). Participants accumulated ~114 min/day of moderate-to-vigorous PA (MVPA) and ~354 min/day of ST during accelerometer wear-time (~828 min/day). The estimated difference in MVPA between participants with the 1st and 3rd quartiles observed values on the composite subjective environmental index of activity-friendliness (perceived land use mix - diversity, street connectivity and aesthetics) was equivalent to ~8 min/day (~56 MVPA min/week) and for the objective environmental index of activity-friendliness (gross residential density and number of parks within 2 km distance from home) was ~6 min of MVPA/day (~45 MVPA min/week). When both indices were entered in a main-effect model, both indices remained significantly correlated with MVPA with sex as a moderator. The predicted difference in sedentary time between those with the minimum and maximum observed values on the subjective index of non-sedentariness was ~20 min/day. CONCLUSIONS: The combined assessment of the main effects of subjective and objective indices of activity-friendliness on NZ adolescents' PA and ST showed positive relationships with MVPA for the subjective index only. The subjective index was a significant correlate of PA in both girls and boys, while the objective index was significant only in boys when sex was entered as a moderator. Further research is warranted to understand the relationships of ST with the built environment.

Built environmental factors and adults' travel behaviors: Role of street layout and local destinations.

Street layout is consistently associated with adults' travel behaviors, however factors influencing this association are unclear. We examined associations of street layout with travel behaviors: walking for transport (WT) and car use; and, the extent to which these relationships may be accounted for by availability of local destinations. A 24-h travel diary was completed in 2009 by 16,345 adult participants of the South-East Queensland Household Travel Survey, Australia. Three travel-behavior outcomes were derived: any home-based WT; over 30min of home-based WT; and, over 60min of car use. For street layout, a space syntax measure of street integration was calculated for each Statistical Area 1 (SA1, the smallest geographic unit in Australia). An objective measure of availability of destinations - Walk Score - was also derived for each SA1. Logistic regression examined associations of street layout with travel behaviors. Mediation analyses examined to what extent availability of destinations explained the associations. Street integration was significantly associated with travel behaviors. Each one-decile increment in street integration was associated with an 18% (95%CI: 1.15, 1.21) higher odds of any home-based WT; a 10% (95%CI: 1.06, 1.15) higher odds of over 30min of home-based WT; and a 5% (95%CI: 0.94, 0.96) lower odds of using a car over 60min. Local destinations partially mediated the effects of street layout on travel behaviors. Well-connected street layout contributes to active travel partially through availability of more local destinations. Urban design strategies need to address street layout and destinations to promote active travel among residents.

International comparison of observation-specific spatial buffers: maximizing the ability to estimate physical activity.

BACKGROUND: Advancements in geographic information systems over the past two decades have increased the specificity by which an individual's neighborhood environment may be spatially defined for physical activity and health research. This study investigated how different types of street network buffering methods compared in measuring a set of commonly used built environment measures (BEMs) and tested their performance on associations with physical activity outcomes. METHODS: An internationally-developed set of objective BEMs using three different spatial buffering techniques were used to evaluate the relative differences in resulting explanatory power on self-reported physical activity outcomes. BEMs were developed in five countries using 'sausage,' 'detailed-trimmed,' and 'detailed,' network buffers at a distance of 1 km around participant household addresses (n = 5883). RESULTS: BEM values were significantly different (p < 0.05) for 96% of sausage versus detailed-trimmed buffer comparisons and 89% of sausage versus detailed network buffer comparisons. Results showed that BEM coefficients in physical activity models did not differ significantly across buffering methods, and in most cases BEM associations with physical activity outcomes had the same level of statistical significance across buffer types. However, BEM coefficients differed in significance for 9% of the sausage versus detailed models, which may warrant further investigation. CONCLUSIONS: Results of this study inform the selection of spatial buffering methods to estimate physical activity outcomes using an internationally consistent set of BEMs. Using three different network-based buffering methods, the findings indicate significant variation among BEM values, however associations with physical activity outcomes were similar across each buffering technique. The study advances knowledge by presenting consistently assessed relationships between three different network buffer types and utilitarian travel, sedentary behavior, and leisure-oriented physical activity outcomes.

Neighborhood environmental attributes and adults' sedentary behaviors: Review and research agenda.

OBJECTIVE: Physical activity recommendations are beginning to address sedentary behaviors - time spent sitting. Environmental and policy initiatives for physical activity might assist in addressing sedentary behaviors, but sedentary-specific innovations may be required. This review synthesizes current evidence on associations of neighborhood environmental attributes with adults' sedentary behaviors. METHODS: A search was conducted using three electronic databases (PubMed, Web of Science, and Transport Research Information Services). Relevant articles were assessed for their eligibility for inclusion (English-language articles with a quantitative examination of associations of neighborhood environmental attributes with adults' sedentary behaviors). RESULTS: Within 17 studies meeting inclusion criteria, associations of environmental attributes with sedentary behaviors were examined in 89 instances. Significant associations were found in 28% (n=25) of them; however, non-significant associations were found in 56% (n=50) of these instances. The most consistent association was for lower levels of sedentary behavior among residents of urban compared to regional areas. CONCLUSIONS: There is a modest but mixed initial evidence in associations of neighborhood environmental attributes with adults' sedentary behaviors. A research agenda required for this emerging field should include the development of more relevant conceptual models, measuring domain-specific sedentary behavior objectively, examining environments in close vicinity of and a larger area around home, and the use of prospective designs.

Mismatch between perceived and objectively measured land use mix and street connectivity: associations with neighborhood walking.

Studies on the mismatch between objective and perceived measures of walkability and walking provide insights into targeting interventions. These studies focused on those living in more walkable environments, but perceiving them as less walkable. However, it is equally important to understand how the other mismatch (living in less walkable areas, but perceiving them as walkable) is related to walking. This study examined how the mismatch between perceived and objective walkability measures (i.e., living in less walkable areas, but perceiving them as walkable, and living in more walkable areas, but perceiving them as less walkable) was associated with walking. Baseline data from adult participants (n = 1466) of the RESIDential Environment Project (Perth, Australia in 2004-06) collected self-report neighborhood walking for recreation and transport in a usual week and participants' perceptions of street connectivity and land use mix in their neighborhood. The exposure was the mismatch between objective and perceived measures of these. Multilevel logistic regression examined associations of walking with the mismatch between perceived and objective walkability measures. Perceiving high walkable attributes as low walkable was associated with lower levels of walking, while perceiving a low walkable attribute as walkable was associated with higher levels of walking. Walking interventions must create more pedestrian-friendly environments as well as target residents' perceptions.

Neighbourhood built environment associations with body size in adults: mediating effects of activity and sedentariness in a cross-sectional study of New Zealand adults.

BACKGROUND: The aim of this study was to determine the associations between body size and built environment walkability variables, as well as the mediating role of physical activity and sedentary behaviours with body size. METHODS: Objective environment, body size (body mass index (BMI), waist circumference (WC)), and sedentary time and physical activity data were collected from a random selection of 2033 adults aged 20-65 years living in 48 neighbourhoods across four New Zealand cities. Multilevel regression models were calculated for each comparison between body size outcome and built environment exposure. RESULTS AND DISCUSSION: Street connectivity and neighborhood destination accessibility were significant predictors of body size (1 SDchange predicted a 1.27 to 1.41 % reduction in BMI and a 1.76 to 2.29 % reduction in WC). Significantrelationships were also observed for streetscape (1 SD change predicted a 1.33 % reduction in BMI) anddwelling density (1 SD change predicted a 1.97 % reduction in BMI). Mediation analyses revealed asignificant mediating effect of physical activity on the relationships between body size and street connectivity and neighbourhood destination accessibility (explaining between 10.4 and 14.6 % of the total effect). No significant mediating effect of sedentary behaviour was found. Findings from this cross-sectional study of a random selection of New Zealand adults are consistent with international research. Findings are limited to individual environment features only; conclusions cannot be drawn about the cumulative and combined effect of individual features on outcomes. CONCLUSIONS: Built environment features were associated with body size in the expected directions. Objectively-assessed physical activity mediated observed built environment-body size relationships.

Environmental and socio-demographic associates of children's active transport to school: a cross-sectional investigation from the URBAN Study.

BACKGROUND: Active transport (e.g., walking, cycling) to school (ATS) can contribute to children's physical activity and health. The built environment is acknowledged as an important factor in understanding children's ATS, alongside parental factors and seasonality. Inconsistencies in methodological approaches exist, and a clear understanding of factors related to ATS remains equivocal. The purpose of this study was to gain a better understanding of associates of children's ATS, by considering the effects of daily weather patterns and neighbourhood walk ability and neighbourhood preferences (i.e., for living in a high or low walkable neighbourhood) on this behaviour. METHODS: Data were drawn from the Understanding Relationships between Activity and Neighbourhoods study, a cross-sectional study of physical activity and the built environment in adults and children in four New Zealand cities. Parents of participating children completed an interview and daily trip diary that assessed their child's mode of travel to school, household and individual demographic information, and parental neighbourhood preference. Daily weather data were downloaded from New Zealand's national climate database. Geographic information systems-derived variables were calculated for distance to school and neighbourhood walkability. Bivariate analyses were conducted with ATS and potential associates; factors related to ATS at p < 0.20 were considered simultaneously in generalized estimation equation models, and backwards elimination of non-significant factors was conducted; city was treated as a fixed effect in all models. RESULTS: A total of 217 children aged 6.5-15 years participated in this study. Female sex, age, city, household income, limited/no car access, residing in zone of school, shorter distance to school, neighbourhood self selection, rainfall, and sunlight hours were simultaneously considered in multivariate generalised estimation equation modelling (all p < 0.20 in bivariate analyses). After elimination of non-significant factors, age (p = 0.005), shorter distance to school (p < 0.001), city (p = 0.03), and neighbourhood self selection (p = 0.04) remained significantly associated with ATS in the multivariate analysis. CONCLUSION: Distance to school is the prevailing environmental influencing factor on children's ATS. This study, in conjunction with previous research, suggests that school siting is likely an important associate of children's ATS.

International variation in neighborhood walkability, transit, and recreation environments using geographic information systems: the IPEN adult study.

BACKGROUND: The World Health Organization recommends strategies to improve urban design, public transportation, and recreation facilities to facilitate physical activity for non-communicable disease prevention for an increasingly urbanized global population. Most evidence supporting environmental associations with physical activity comes from single countries or regions with limited variation in urban form. This paper documents variation in comparable built environment features across countries from diverse regions. METHODS: The International Physical Activity and the Environment Network (IPEN) study of adults aimed to measure the full range of variation in the built environment using geographic information systems (GIS) across 12 countries on 5 continents. Investigators in Australia, Belgium, Brazil, Colombia, the Czech Republic, Denmark, China, Mexico, New Zealand, Spain, the United Kingdom, and the United States followed a common research protocol to develop internationally comparable measures. Using detailed instructions, GIS-based measures included features such as walkability (i.e., residential density, street connectivity, mix of land uses), and access to public transit, parks, and private recreation facilities around each participant's residential address using 1-km and 500-m street network buffers. RESULTS: Eleven of 12 countries and 15 cities had objective GIS data on built environment features. We observed a 38-fold difference in median residential densities, a 5-fold difference in median intersection densities and an 18-fold difference in median park densities. Hong Kong had the highest and North Shore, New Zealand had the lowest median walkability index values, representing a difference of 9 standard deviations in GIS-measured walkability. CONCLUSIONS: Results show that comparable measures can be created across a range of cultural settings revealing profound global differences in urban form relevant to physical activity. These measures allow cities to be ranked more precisely than previously possible. The highly variable measures of urban form will be used to explain individuals' physical activity, sedentary behaviors, body mass index, and other health outcomes on an international basis. Present measures provide the ability to estimate dose-response relationships from projected changes to the built environment that would otherwise be impossible.