Associations between gentrification, census tract-level socioeconomic status, and cycling infrastructure expansions in Montreal, Canada.

Background: Cycling infrastructure investments support active transportation, improve population health, and reduce health inequities. This study examines the relationship between changes in cycling infrastructure (2011-2016) and census tract (CT)-level measures of material deprivation, visible minorities, and gentrification in Montreal. Methods: Our outcomes are the length of protected bike lanes, cyclist-only paths, multi-use paths, and on-street bike lanes in 2011, and change in total length of bike lanes between 2011 and 2016 at the CT level. Census data provided measures of the level of material deprivation and of the percentage of visible minorities in 2011, and if a CT gentrified between 2011 and 2016. Using a hurdle modeling approach, we explore associations among these CT-level socioeconomic measures, gentrification status, baseline cycling infrastructure (2011), and its changes (2011-2016). We further tested if these associations varied depending on the baseline level of existing infrastructure, to assess if areas with originally less resources benefited less or more. Results: In 2011, CTs with higher level of material deprivation or greater percentages of visible minorities had less cycling infrastructure. Overall, between 2011 and 2016, cycling infrastructure increased from 7.0% to 10.9% of the road network, but the implementation of new cycling infrastructure in CTs with no pre-existing cycling infrastructure in 2011 was less likely to occur in CTs with a higher percentage of visible minorities. High-income CTs that were ineligible for gentrification between 2011 and 2016 benefited less from new cycling infrastructure implementations compared to low-income CTs that were not gentrified during the same period. Conclusion: Montreal's municipal cycling infrastructure programs did not exacerbate socioeconomic disparities in cycling infrastructure from 2011 to 2016 in CTs with pre-existing infrastructure. However, it is crucial to prioritize the implementation of cycling infrastructure in CTs with high populations of visible minorities, particularly in CTs where no cycling infrastructure currently exists.

Aircraft noise and environmental equity in Montréal: A comparison of noise indicators and an analysis of the impacts of COVID-19.

From an environmental equity perspective, the aim of this paper is twofold. First, we want to verify to what extent vulnerable population groups resided in areas exposed to high levels of aircraft noise before and during the COVID-19 pandemic (2019 and 2020) in the Montréal census metropolitan area. Second, we want to identify whether the use of an aircraft noise indicator rather than another generates significant variations in the results and consequently in terms of affected areas and populations. With the IMPACT web-application, we model aircraft noise contours from three cumulative (Lden , Ldn , Laeq ,24h) and a single-event (LAmax ) metrics. The model's input data are retrieved by a website for flight tracking. Next, four variables are extracted from the 2016 Statistics Canada census at a fine scale level (dissemination areas): that is, the percentages of low-income individuals, visible minorities, children under 15 years old, and individuals aged 65 and over. The results show a significant drop in population exposed to aircraft noise in 2020 compared to 2019. In addition, the estimates of populations impacted by aircraft noise differ from one indicator to the next. The logistic regression models indicate that the inequities are inconsistent between cumulative and single-event metrics.

One Metre Plus (1M+): A Multifunctional Open-Source Sensor for Bicycles Based on Raspberry Pi.

During the last decade, bicycles equipped with sensors became an essential tool for research, particularly for studies analyzing the lateral passing distance between motorized vehicles and bicycles. The objective of this article is to describe a low-cost open-source sensor called one metre plus (1m+) capable of measuring lateral passing distance, registering the geographical position of the cyclist, and video-recording the trip. The plans, codes, and schematic design are open and therefore easily accessible for the scientific community. This study describes in detail the conceptualization process, the characteristics of the device, and the materials from which they are made. The study also provides an evaluation of the product and describes the sensor's functionalities and its field of application. The objective of this project is to democratize research and develop a platform/participative project that offers tools to researchers worldwide, in order to standardize knowledge sharing and facilitate the comparability of results in various contexts.

Cycling in one of the most polluted cities in the world: Exposure to noise and air pollution and potential adverse health impacts in Delhi.

BACKGROUND: In India, many cities struggle with extreme levels of air pollution and noise. Delhi, in particular, has the notorious reputation of being one of the most polluted cities in the world. Cyclists constitute a particularly exposed population, since they cycle among motor vehicles without any protection. This paper modeled the cyclists' exposure to nitrogen dioxide (NO2) and noise in Delhi, India. METHODS: Using primary data collected on 1,229 kms of roads in Delhi, Generalized Additive Mixed Models with Auto-Regressive terms (GAMMAR) are constructed for noise exposure, NO2 exposure and NO2 inhalation doses. RESULTS: Results show that cyclists are exposed to 47 µg/m3 of NO2 and 3.3 dB(A) more when cycling on a primary road than on a residential street. Using WHO guideline values for noise and air pollution, we assessed how many minutes of inhaling doses and noise doses become potentially harmful to cyclists' health in Delhi. Such thresholds are quickly exceeded: after cycling one hour in an area with moderate predicted values of noise and air pollution, the noise dose and inhaled dose of NO2 will reach 212% and 403 µg on residential streets, and 459% and 482 µg on primary roads, respectively. CONCLUSION: Policy makers should take these results into account to minimize cyclists' exposure, especially for the most deprived people.

Short-Term Impact of Traffic-Related Particulate Matter and Noise Exposure on Cardiac Function.

Exposure to traffic-related air pollution and noise exposure contributes to detrimental effects on cardiac function, but the underlying short-term effects related to their simultaneous personal exposure remain uncertain. The aim is to assess the impact of total inhaled dose of particulate matter and total noise exposure on the variations of electrocardiogram (ECG) parameters between pre-cycling and post-cycling periods. Mid-June 2019, we collected four participants' personal exposure data related to traffic-related noise and particulate matter (PM2.5 and PM10) as well as ECG parameters. Several Bayesian linear models were built to examine a potential association between air pollutants and noise exposure and ECG parameters: heart rate (HR), standard deviation of the normal-to-normal intervals (SDNN), percentage of successive RR intervals that differ by more than 50 ms (pNN50), root mean square of successive RR interval differences (rMSSD), low-frequency power (LF), high-frequency power (HF), and ratio of low- to high-frequency power (LF/HF). We analyzed in total 255 5-min segments of RR intervals. We observed that per 1 µg increase in cumulative inhaled dose of PM2.5 was associated with 0.48 (95% CI: 0.22; 15.61) increase in variation of the heart rate, while one percent of total noise dose was associated with 0.49 (95% CI: 0.17; 0.83) increase in variation of heart rate between corresponding periods. Personal noise exposure was no longer significant once the PM2.5 was introduced in the whole model, whilst coefficients of the latter that were significant previously remained unchanged. Short-term exposure to traffic-related air and noise pollution did not, however, have an impact on heart rate variability.

Cross-border spatial accessibility of health care in the North-East Department of Haiti.

BACKGROUND: The geographical accessibility of health services is an important issue especially in developing countries and even more for those sharing a border as for Haiti and the Dominican Republic. During the last 2 decades, numerous studies have explored the potential spatial access to health services within a whole country or metropolitan area. However, the impacts of the border on the access to health resources between two countries have been less explored. The aim of this paper is to measure the impact of the border on the accessibility to health services for Haitian people living close to the Haitian-Dominican border. METHODS: To do this, the widely employed enhanced two-step floating catchment area (E2SFCA) method is applied. Four scenarios simulate different levels of openness of the border. Statistical analysis are conducted to assess the differences and variation in the E2SFCA results. A linear regression model is also used to predict the accessibility to health care services according to the mentioned scenarios. RESULTS: The results show that the health professional-to-population accessibility ratio is higher for the Haitian side when the border is open than when it is closed, suggesting an important border impact on Haitians' access to health care resources. On the other hand, when the border is closed, the potential accessibility for health services is higher for the Dominicans. CONCLUSION: The openness of the border has a great impact on the spatial accessibility to health care for the population living next to the border and those living nearby a road network in good conditions. Those findings therefore point to the need for effective and efficient trans-border cooperation between health authorities and health facilities. Future research is necessary to explore the determinants of cross-border health care and offers an insight on the spatial revealed access which could lead to a better understanding of the patients' behavior.

The approaches to measuring the potential spatial access to urban health services revisited: distance types and aggregation-error issues.

BACKGROUND: The potential spatial access to urban health services is an important issue in health geography, spatial epidemiology and public health. Computing geographical accessibility measures for residential areas (e.g. census tracts) depends on a type of distance, a method of aggregation, and a measure of accessibility. The aim of this paper is to compare discrepancies in results for the geographical accessibility of health services computed using six distance types (Euclidean and Manhattan distances; shortest network time on foot, by bicycle, by public transit, and by car), four aggregation methods, and fourteen accessibility measures. METHODS: To explore variations in results according to the six types of distance and the aggregation methods, correlation analyses are performed. To measure how the assessment of potential spatial access varies according to three parameters (type of distance, aggregation method, and accessibility measure), sensitivity analysis (SA) and uncertainty analysis (UA) are conducted. RESULTS: First, independently of the type of distance used except for shortest network time by public transit, the results are globally similar (correlation >0.90). However, important local variations in correlation between Cartesian and the four shortest network time distances are observed, notably in suburban areas where Cartesian distances are less precise. Second, the choice of the aggregation method is also important: compared with the most accurate aggregation method, accessibility measures computed from census tract centroids, though not inaccurate, yield important measurement errors for 10% of census tracts. Third, the SA results show that the evaluation of potential geographic access may vary a great deal depending on the accessibility measure and, to a lesser degree, the type of distance and aggregation method. Fourth, the UA results clearly indicate areas of strong uncertainty in suburban areas, whereas central neighbourhoods show lower levels of uncertainty. CONCLUSION: In order to accurately assess potential geographic access to health services in urban areas, it is particularly important to choose a precise type of distance and aggregation method. Then, depending on the research objectives, the choices of the type of network distance (according to the mode of transportation) and of a number of accessibility measures should be carefully considered and adequately justified.

Neighborhood characteristics associated with the availability of alcohol outlets in quebec, Canada.

Objectives. The objectives of this study were to examine the spatial accessibility to alcohol outlets in Quebec and to assess the association between neighborhood level characteristics and availability of alcohol outlets. Methods. The Tobit Model was used to assess the association between neighborhood level characteristics and the availability of alcohol outlets within 500, 1000, 2000, and 3000 metres, respectively. Results. Alcohol outlets were found to be most available in the two largest metropolitan areas of the province of Quebec (Montréal and Québec City). Within 1000 metres, alcohol outlets are more available in neighbourhoods with the following characteristics: highest concentration of men, least materially deprived highest concentration of persons aged 20 years or more, and location either in a metropolitan area or in a small town. Finally, the number of bars with video lottery terminals increases with the level of social and material deprivation. Conclusion. In Québec, there is no rule governing the location of alcohol outlets. Thus, there is an abundant literature indicating that the regulation of alcohol outlet density could be an effective means of controlling risk attributable to alcohol consumption.

Cannabis cultivation in Quebec: between space-time hotspots and coldspots.

BACKGROUND: Cannabis cultivation has become increasingly localized, whether soil-based or hydroponic growing methods are used. Characteristics of a given location, such as its climate and the equipment it requires may influence general accessibility or attract different types of offenders based on potential profits. The location of crops, especially hydroponic crops, suggests a certain proximity to the consumer market via semi-urban and urban environments, while making it possible to avoid detection. This article examines the cannabis market through its cultivation. METHODS: The stability of temporal and spatial clusters of cannabis cultivation, hotspots, and coldspots between 2001 and 2009 in the province of Quebec, Canada, are addressed. Studying the geography of crime is not a new endeavor, but coldspots are rarely documented in drug market research. Using arrests and general population data, as well as Kulldorff's scan statistics, results show that the temporal distribution of cannabis cultivation is highly seasonal for soil-based methods. RESULTS: Hydroponic production shows adaptation to its soil-based counterpart. Stable patterns are found for both spatial distributions. Hotspots for soil-based cultivation are found near several urban centers and the Ontario border. For hydroponic cannabis cultivation, a new hotspot suggests the emergence of an American demand for Quebec-grown cannabis between 2007 and 2009. Curiously, the region surrounding Montreal, the largest urban center in Quebec, is a recurrent and stable coldspot for both methods of cultivation. CONCLUSION: For all periods, spatial clusters are stronger for soil-based methods than in the hydroponic context. Temporal differences and spatial similarities between soil-based cultivation and hydroponic cultivation are discussed. The role of the metropolis is also addressed.

Spatial analysis of suicide mortality in Québec: spatial clustering and area factor correlates.

Understanding the spatial distribution of suicide can inform the planning, implementation and evaluation of suicide prevention actions. No previous study has assessed spatial clustering of the different methods of suicide in Quebec. The aim of this study was to assess spatial clustering of suicide in Quebec between 2004 and 2007 and neighborhood level predictors of the clusters. Scan statistics was applied to detect clusters of suicides by method and by sex. Smoothed standardized mortality ratios (SMRs) for suicide for each neighborhood were also estimated and their association with neighborhood characteristics was investigated using the Bayesian hierarchical spatial model. The pattern of suicide rate was different among men and women; men showed higher standardized mortality rates. The most likely clusters of suicide were found in remote rural areas. However, some neighborhoods in urban areas also had noticeable suicide clusters. Firearms suicide was most likely found in remote rural areas while poisoning and hanging suicide methods clustered in urban areas. These findings suggest that it is important to take geographical variations into account in national policy and health services planning.

Geographic analysis of infant mortality in New Zealand, 1995-2008: an ethnicity perspective.

OBJECTIVE: To detect spatial clusters of high infant mortality rates in New Zealand for Maori and non-Maori populations and verify if these clusters are stable over a certain time period (1995-2008) and similar between the two populations. METHOD: We applied the Kulldorff's spatial scan statistics on data collected by New Zealand Ministry of Health (1995 to 2008) at the territorial local authorities (TLA) level. Kappa coefficient was used to assess the concordance between clusters obtained for Maori and non-Maori populations. T-test analyses were conducted to identify associations between spatial clusters and two predictors (population density and deprivation score). RESULTS: There are some significant spatial clusters of infant mortality in New Zealand for both Maori and Non-Maori. The concordance of the cluster locations between the two populations is strong (kappa=0.77). Unsurprisingly, infant mortality clusters for both Maori and Non-Maori are associated with the deprivation score. The population density predictor is only significantly and positively associated with clusters obtained for the non-Maori population. After controlling for deprivation the presence of spatial clusters is all but eliminated. CONCLUSIONS: Infant mortality patterns are geographically similar for both Maori and Non-Maori. However, there are differences geographically between the two populations after accounting for deprivation. IMPLICATIONS: Health services that can affect infant mortality should be aware of the geographical differences across NZ. Deprivation is an important factor in explaining infant mortality rates and policies that ameliorate its effects should be pursued, as it is the major determinant of the geographical pattern of infant mortality in NZ.

Disentangling the influence of neighborhood and individual characteristics on early residential mobility among newly diagnosed patients with schizophrenia: a multilevel analysis.

PURPOSE: Early residential mobility of schizophrenic patients may relate to discontinuity of treatment and adverse outcome. However, factors influencing early residential mobility of these patients are still poorly examined. The aim of this study was to disentangle the influence of individual and neighborhood characteristics on early residential mobility of schizophrenic patients. METHODS: The study used administrative data of 13, 400 individuals newly diagnosed with schizophrenia in Quebec between 2001 and 2002. These individuals were nested in 163 different health territories. Multilevel analyses were used to assess the contribution of individual and neighborhood characteristics on early residential mobility. RESULTS: The final model indicates that at the individual level, being men, wonder patients and physical comorbidity increased the likelihood of early residential mobility whereas older patients were less likely to migrate earlier. The health territory level explains about 7 % of the variation of early residential mobility and variables influencing residential mobility at this level are the fourth and the third quartiles of the population density. CONCLUSIONS: Factors influencing early residential mobility of schizophrenic patients are located at both individual and neighborhood levels. This suggests that policies targeting only one-level factors are unlikely to significantly delays early residential mobility.

Exploring hotspots of pneumococcal pneumonia and potential impacts of ejecta dust exposure following the Christchurch earthquakes.

The etiology of pneumococcal pneumonia (PP) is well-known. Yet, some events may increase its incidence. Natural disasters may worsen air quality, a risk factor for PP. We investigated spatial/spatio-temporal clustering of PP pre- and post-earthquakes in Christchurch, New Zealand. The earthquakes resulted in deaths, widespread damage and liquefaction ejecta (a source of air-borne dust). We tested for clusters and associations with ejecta, using 97 cases (diagnosed 10/2008-12/2011), adjusted for age and area-level deprivation. The strongest evidence to support the potential role of ejecta in clusters of PP cases was the: (1) geographic shift in the spatio-temporal cluster after deprivation adjustment to match the post-earthquake clusters and; (2) increased relative risk in the fully-adjusted post-earthquake compared to the pre-earthquake cluster. The application of spatial statistics to study PP and ejecta are novel. Further studies to assess the long-term impacts of ejecta inhalation are recommended particularly in Christchurch, where seismic activity continues.

Spatio-temporal clustering of the incidence of schizophrenia in Quebec, Canada from 2004 to 2007.

Exploring spatio-temporal patterns of disease incidence can help to identify areas of significantly elevated or decreased risk, providing potential etiologic clues. In this study, we present a spatio-temporal analysis of the incidence of schizophrenia in Quebec from 2004 to 2007 using administrative databases from the Régie de l'Assurance Maladie du Quebec and the hospital discharge database. We conducted purely spatial analyses for each age group adjusted by sex for the whole period using SatScan (version 9.1.1). Findings from the study indicated variations in the spatial clustering of schizophrenia according to sex and age. In term of incidence rate, there are high differences between urban and rural-remote areas, as well as between the two main metropolitan areas of the province of Quebec (Island of Montreal and Quebec-City).

Cumulative disadvantage? Exploring relationships between neighbourhood deprivation trends (1991 to 2006) and mortality in New Zealand.

BACKGROUND: Area-level socioeconomic deprivation has been shown to exert an independent effect on both individual and population health outcomes and health-related behaviours. Evidence also suggests that health and economic inequalities in many countries are increasing in some areas but may be on the decline in others. While area-level deprivation at a single point in time is known to influence health, the literature relating to longitudinal deprivation of communities and associated health impacts is sparse. This research makes a methodological contribution to this literature. METHODS: Using a Latent Class Growth Model, we identified 12 deprivation trends (1991-2006) for small areas (n = 1621) in New Zealand. We then fitted regression models to assess the effects of trends of relative deprivation on a) all-cause mortality, and b) cardiovascular mortality (2005-2007) by census area unit. For comparison, we also fitted regression models to assess the effect of deprivation deciles (in 2006) on outcomes a) and b). RESULTS: Using trends, we found a positive association between deprivation and mortality, except for two trends for both all-cause and CVD-related mortality. When comparing trends and deciles of deprivation, we observed similar patterns. However, we found that AIC values were slightly lower for the model including deciles, indicating better model fit. CONCLUSION: While we found that current deprivation was a slightly better predictor of mortality, the approach used here offers a potentially useful alternative. Future deprivation research must consider the possible loss of information about health benefits of living in areas where relative deprivation has improved in cross-sectional analyses.

Regional variation in the modeling of donation frequency: the case of Héma-Québec, Canada.

BACKGROUND: Many studies on factors that can affect the frequency of blood donation have shown the influence of several individual characteristics. However, few studies have analyzed regional variations in blood donation frequency. The objective of this article is to verify to what extent individual and geographic variables influence blood donation in the Province of Québec, Canada. STUDY DESIGN AND METHODS: This article used a database provided by Héma-Québec (the organization in charge of blood collection in Québec), which included 426,247 donors, who made 1.4 million donations over a period of 5 years. Using the donors' residential postal codes and those of the blood collection sites, we created two geographic variables: the distance between the donor's place of residence and his or her collection site and each donor's region of residence. We subsequently modeled the frequency of blood donation and the different donor categories (based on the number of blood donations) using both a negative binomial regression model and an ordinal logistic regression model. RESULTS: The results indicate that, once the individual characteristics have been taken into account, the geographic variables, including proximity to the collection site, have a significant impact on the frequency of blood donation. Likewise, according to the results of the negative binomial model, among the 17 regions in the Province of Québec, there are five regions where blood donation incidence rate ratios (IRRs) are very high, that is, Abitibi-Témiscamingue (IRR, 1.77; 95% confidence interval [CI], 1.61-1.95); Bas-Saint-Laurent (IRR, 1.75; 95% CI, 1.59-1.93); Saguenay-Lac-Saint-Jean (IRR, 1.68; 95% CI, 1.53-1.84); Centre-du-Québec (IRR, 1.66; 95% CI, 1.51-1.83); and Chaudière-Appalaches (IRR, 1.62; 95% CI, 1.48-1.78). CONCLUSION: Such knowledge of the geography of blood donations makes it possible to better target certain regions when planning new blood drives, to ensure a constant blood supply.

Classifying neighbourhoods by level of access to stores selling fresh fruit and vegetables and groceries: identifying problematic areas in the city of Gatineau, Quebec.

OBJECTIVES: Physical access to stores selling groceries, fresh fruit and vegetables (FV) is essential for urban dwellers. In Canadian cities where low-density development practices are common, social and material deprivation may be compounded by poor geographic access to healthy food. This case study examines access to food stores selling fresh FV in Gatineau, Quebec, to identify areas where poor access is coincident with high deprivation. METHOD: Food retailers were identified using two secondary sources and each store was visited to establish the total surface area devoted to the sale of fresh FV. Four population-weighted accessibility measures were then calculated for each dissemination area (DA) using road network distances. A deprivation index was created using variables from the 2006 Statistics Canada census, also at the scale of the DA. Finally, six classes of accessibility to a healthy diet were constructed using a k-means classification procedure. These were mapped and superimposed over high deprivation areas. RESULTS: Overall, deprivation is positively correlated with better accessibility. However, more than 18,000 residents (7.5% of the population) live in high deprivation areas characterized by large distances to the nearest retail food store (means of 1.4 km or greater) and virtually no access to fresh FV within walking distance (radius of 1 km). CONCLUSION: In this research, we identified areas where poor geographic access may introduce an additional constraint for residents already dealing with the challenges of limited financial and social resources. Our results may help guide local food security policies and initiatives.

Optimizing the two-step floating catchment area method for measuring spatial accessibility to medical clinics in Montreal.

BACKGROUND: Reducing spatial access disparities to healthcare services is a growing priority for healthcare planners especially among developed countries with aging populations. There is thus a pressing need to determine which populations do not enjoy access to healthcare, yet efforts to quantify such disparities in spatial accessibility have been hampered by a lack of satisfactory measurements and methods. This study compares an optimised and the conventional version of the two-step floating catchment area (2SFCA) method to assess spatial accessibility to medical clinics in Montreal. METHODS: We first computed catchments around existing medical clinics of Montreal Island based on the shortest network distance. Population nested in dissemination areas were used to determine potential users of a given medical clinic. To optimize the method, medical clinics (supply) were weighted by the number of physicians working in each clinic, while the previous year's medical clinic users were computed by ten years age group was used as weighting coefficient for potential users of each medical clinic (demand). RESULTS: The spatial accessibility score (SA) increased considerably with the optimisation method. Within a distance of 1 Km, for instance, the maximum clinic accessible for 1,000 persons is 2.4 when the conventional method is used, compared with 27.7 for the optimized method. The t-test indicates a significant difference between the conventional and the optimized 2SFCA methods. Also, results of the differences between the two methods reveal a clustering of residuals when distance increases. In other words, a low threshold would be associated with a lack of precision. CONCLUSION: Results of this study suggest that a greater effort must be made ameliorate spatial accessibility to medical clinics in Montreal. To ensure that health resources are allocated in the interest of the population, health planners and the government should consider a strategy in the sitting of future clinics which would provide spatial access to the greatest number of people.

Predictors of parental risk perceptions: the case of child pedestrian injuries in school context.

The objective of this article is to explore the factors that influence parental risk perceptions of child pedestrian injuries in the elementary school context. Parents (n=193) from six different schools responded to a questionnaire on road safety, including a measure of their risk perception. Results of bivariate analyses show that eight variables are significantly related to risk perception. Environmental variables, as we measure them, were not significant, contrary to our initial hypotheses. Only three variables, parent's gender, perceived primary source of danger, and sense of control remained significant in OLS regression analyses (adjusted R(2) of 0.16, F=9.27; p=0.00). Since parents' perceptions of road risks are an important factor in their road safety practices and in their choice of transportation mode used for their child's journey to school, our analysis elucidates factors underlying these choices. Our results can help decisionmakers to design traffic injury prevention measures and to promote physical activity through the use of active modes of transport.

Disentangling the relative influence of built and socioeconomic environments on walking: the contribution of areas homogenous along exposures of interest.

The geography of small areas has important implications for studying the contextual determinants of health because of potential errors when measuring ecologic exposures and estimating their effects on health. In this paper, we present an approach for designing homogeneous zones optimising the spatial distribution of an area-level exposure, active living potential (ALP), based on data collected in Montreal, Canada. The objectives are to (1) assess and compare variation in walking behaviours between these purposefully designed zones and between standard administrative units, census tracts; and (2) disentangle the relative influence of ALP and area-level socioeconomic conditions on walking using the alternative geographies. Zones were designed by statistically classifying smallest census areas (disseminations areas) into seven categories of exposure similar along three indicators of ALP: population density, land use mix, and geographic accessibility to services. Mapping of categories resulted in the delineation of zones characterised by one of seven levels of ALP. A sample of 2716 adults aged >/=45 years was geocoded and cross-classified in 270 zones and 112 census tracts. Individuals reported on minutes and motives of walking and provided socioeconomic information. Data were analysed using cross-classified multilevel models. Variation in utilitarian walking was larger across the purposefully defined zones than across census tracts. Total walking varied significantly between census tracts only. Greater ALP was associated with more utilitarian walking but with less recreational walking. Higher socioeconomic position in census tracts was positively associated with total, utilitarian, and recreational walking. The soundness of standard administrative units for measuring ecologic exposure and their associations with health should be considered prior to conducting analyses. The added value of different approaches for understanding how place relates to health remains to be established and should be the focus of further investigations.