Capturing exposure in environmental health research: challenges and opportunities of different activity space models

Abstract

BackgroundThe built environment health promotion has attracted notable attention across a wide spectrum of health-related research over the past decade. However, the results about the contextual effects on health and PA are highly heterogeneous. The discrepancies between the results can potentially be partly explained by the diverse use of different spatial units of analysis in assessing individuals’ exposure to various environment characteristics. This study investigated whether different residential and activity space units of analysis yield distinct results regarding the association between the built environment and health. In addition, this study examines the challenges and opportunities of the different spatial units of analysis for environmental health-related research.MethodsTwo common residential units of analysis and two novel activity space models were used to examine older adults’ wellbeing in relation to the built environment features in the Helsinki Metropolitan Area, Finland. An administrative unit, 500 m residential buffer, home range model and individualized residential exposure model were used to assess the associations between the built environment and wellbeing of respondent’s (n = 844).ResultsAll four different spatial units of analysis yield distinct results regarding the associations between the built environment characteristics and wellbeing. A positive association between green space and health was found only when exposure was assessed with individualized residential exposure model. Walkability index and the length of pedestrian and bicycle roads were found to positively correlate with perceived wellbeing measures only with a home range model. Additionally, all units of analysis differed from each other in terms of size, shape, and how they capture different contextual measures.ConclusionsThe results show that different spatial units of analysis result in considerably different measurements of built environment. In turn, the differences derived from the use of different spatial units seem to considerably affect the associations between environment characteristics and wellbeing measures. Although it is not easy to argue about the correctness of these measurements, what is evident is that they can reveal different wellbeing outcomes. While some methods are especially usable to determine the availability of environmental opportunities that promote active travel and the related health outcomes, others can provide us with insight into the mechanisms how the actual exposure to green structure can enhance wellbeing.

Shopping trip mode choice of older adults: an application of activity space and hybrid choice models in understanding the effects of built environment and personal goals

“…The validity of the use of commonly used buffers to account for the effect of built environment on individuals' travel behavior has, therefore, become controversial (e.g. Perchoux et al 2013;Holliday et al 2017;Laatikainen et al 2018). Such predefined spatial units of analysis have been criticized for not being able to define the spatiotemporal extents of individuals' neighborhoods and spatial exposure (e.g.…”

“…Such predefined spatial units of analysis have been criticized for not being able to define the spatiotemporal extents of individuals' neighborhoods and spatial exposure (e.g. Mitra and Buliung 2012;Perchoux et al 2013;Holliday et al 2017;Laatikainen et al 2018). As Hasanzadeh et al (2017) put it, although the use of buffer has priority over the traditionally rigid neighborhood definitions (such as large traffic analysis zones or administrative boundaries), such definition of neighborhood is individual-centered, but not individual specific for the spatial extent of neighborhood is systematically defined in a uniform way for all individuals.…”

“…activity space models) in addition to the commonly used 500-m buffer in studying the effect of urban form factors on transportation mode choice. Two recently developed activity space modelling methods, individual home range (Hasanzadeh et al 2017) and individualized residential exposure model (Hasanzadeh et al 2018;Hasanzadeh 2018), are used to define person based spatial units of analysis based on respondents' revealed daily activities (Laatikainen et al 2018). To the authors' knowledge, this is the first study that uses these activity space models in studying the effect of urban form factors on transportation mode choice of older adults.…”

Novel green space measures and birthweight in Queensland, Australia

“…It is been shown that differing spatial measurement methods in built environment research can lead to different results for the same exposure-outcome pair. 307 The results of the current study are similar to results from previous work using a range of spatial measurements, which allows more confidence that the findings have not been unduly influenced by the spatial units available. A further limitation on the use of locality as the spatial unit is that locality boundaries may have changed over the duration of the study, and this cannot be accounted for in this study.…”

Risk of late cervical cancer screening according to prosperity and medical density in daily frequented neighborhoods in Greater Paris.

“…Real-time geolocation data (e.g. those acquired by GPS sensors in smartphones) permit a detailed description for activity spaces for equipped individuals [26], but the complexity of these analyses [27][28][29][30] calls for a simplified approach for public health studies.…”