Analysis of BRT Systems and its Implications on Physical Activity Using a Hurdle Model Statistical Approach
Alejandro Perez Villasenor, McGill UniversityShow Abstract
Marco Lopez Castro, McGill University
Annie Chang, McGill University
Benjamin Welle, World Resources Institute
Luis Miranda-Moreno, McGill University
In recent years, researchers have explored the relationship between physical activity and public transit availability. While evidence suggests an increase in physical activity linked to public transit, research regarding this change to changes in transportation mode is scarce. Many studies focus on BRT systems, popular among emerging economies. Using data from Rio de Janeiro's TransCarioca, and Mexico City's Metrobus, we investigate the effects of a new BRT service on physical activity of catchment area residents. A problem related with traffic project evaluation research is that interviewed subjects in pre and post periods are not the same; hence, some research groups have applied propensity score matching techniques to reduce bias and achieve systematic concordance between treatment and control groups. A limitation of this methodology is that it does not consider zero-inflated responses, thus lacking accuracy while estimating the average treatment effect. We present a novel approach in which we conduct a matching process to build the after mentioned groups, and then we use a hurdle statistical model in which the two processes generating the zeros and the positives are not constrained to be the same. Preliminary results show a statistically significant effect of Mexico City's Metrobus system implementation over physical activity, while Rio de Janeiro experiences an increase in the same area after TransCarioca system implementation, although in this case the transport-mode change is statistically not-significant.
How Does Self-Assessed Health Status Relate to Preferences for Cycling Infrastructure? A Latent Class and Latent Variable Approach
Tomas Rossetti (firstname.lastname@example.org), Cornell UniversityShow Abstract
Ricardo Daziano, Cornell University
This study aims to understand how self-assessed health status relates to preferences for cycling infrastructure. An integrated latent class and latent variable choice model is fitted using responses to a stated preference experiment from a panel of New York City residents (N = 801). Estimates show that people with stated good physical health tend to have preference parameters similar to those of experienced cyclists. This result means that the provision of cycling infrastructure with the purpose of attracting non-cyclists also has the potential of attracting those with worse health outcomes. This result suggests a double benefit coming from car use reduction and lower health spending.
High-Resolution Cumulative Exposure Assessment of Traffic-Related Air Pollution with Different Google Navigation Route Options
Minmeng Tang (email@example.com), University of California, DavisShow Abstract
Deb Niemeier, University of Maryland, College Park
We calculate exposure concentrations of traffic-related air pollutants for different traffic modes in the urban environment. We simulate 5,000 trips in Oakland California, US and calculate the exposure concentrations of nitric oxide (NO), nitrogen dioxide (NO2), and black carbon (BC) using high-resolution sensor measured air pollution concentration data. These data were collected by Aclima and Google. For each bicycle, transit and vehicle trip simulation, we calculate the average concentrations and the cumulative exposure of all three pollutants. The cumulative exposure is calculated as the total mass of pollutants being inhaled within the trip. Our results show that cumulative exposure is a more useful metric to assess travel pollutant exposure than average concentration, which is typical in the literature. For all three traffic modes, the average concentrations of each trip are not significantly different. But due to the trip duration and route variations for different traffic modes and the inhalation rates, the cumulative exposure of different traffic modes varies dramatically. Cumulative exposure for those in vehicles tends to be lowest, as well as having the lowest average per meter and per minute exposure based on all simulated trips. Bicyclists and public transit users tend to experience higher cumulative exposures because of the increased inhalation rate and the longer trip duration, respectively. Last but not least, our study shows that total trip duration is more important than total trip distance for air pollution exposure; the shortest duration routes also tend to produce less air pollution exposure than the shortest distance route.
Linking Microscopic Built Environment with Objectively Measured Physical Activity and Health Care Expenditures from an Integrated Health Care System
Behram Wali (firstname.lastname@example.org), Urban Design 4 Health, Inc.Show Abstract
Lawrence Frank, Urban Design 4 Health, Inc.
Deborah Young, Kaiser Permanente Southern California
Brian Saelens, University of Washington
Richard Meenan, Kaiser Permanente Northwest
John Dickerson, Kaiser Permanente Northwest
Erin Keast, Kaiser Permanente Northwest
Jennifer Kuntz, Kaiser Permanente Northwest
Stephen Fortmann, Kaiser Permanente Northwest
No study to date has effectively linked health care utilization and costs with objective assessment of built environment and mode-specific physical activity. We examined how detailed urban form (within the home neighborhood) relates to objectively measured physical activity (PA) and health care costs while controlling for transit access, residential choices, attitudes/preferences, and sociodemographic factors. Unique and high-resolution data are harnessed for 476 participants in the Rails & Health study on health care costs, objective PA and travel behavior, built environment, and transportation/neighborhood perception surveys. Owing to the important methodological issue of potential dependencies among PA and health care cost outcomes arising from observed and unobserved factors, we used structural equation modeling (SEM). The direct effects of objectively measured built environment and PA on health care costs and the indirect effects of built environment on health costs mediated by mode-specific PA are quantified. A 1% increase in bike, walk, and transit-related moderate-to-vigorous PA (MVPA) was associated with lower health care costs by -0.28, -0.09, and -0.27 percent respectively (over a one-year period). A one-unit increase in walkability index (composite measure of intersection density, commercial floor area ratio, and land use mix) was associated with a substantial 6.48% reduction in health care costs. Significant indirect dependencies between residential choices, attitudes, preferences and health outcomes through physical activity were also observed. Methodologically, the results underscore the importance of accounting for unobserved factors that could jointly increase or decrease the mode-specific MVPA outcomes of a same participant.
Social Network Analysis of Public Health Knowledge Domains in the Transportation Research Board
Yicong Yang (email@example.com), University of Wisconsin, MadisonShow Abstract
Carolyn McAndrews, University of Wisconsin, Madison
Although public health and transportation share common interests and have institutionalized some of their shared knowledge, the disciplines do not necessarily align. Researchers and practitioners often point to their mismatched data and different lexicons as opportunities to bring the fields closer together. In this study, we explore the structure of public health knowledge within transportation, examining the alignment among eight topics such as safety, air quality, and equity as well as distinctions between them. We used social network analysis to analyze the presence of these terms in research needs statements written by TRB standing committees between late 2006 to mid–2018. We found that they form a prevalent, interconnected conversation about health within transportation. About half of the records included health-related terms. However, relatively few research needs statements used “health” or “public health” in their vocabulary. In fact, transportation practitioners also used health metaphorically to describe transportation infrastructure. This implies that health is simultaneously well represented in transportation whereas its definition is unsettled.
Transportation Health and Safety Policies - Beyond Automobile Crashes and Climate Change
Yeganeh Hayeri, Stevens Institute of TechnologyShow Abstract
Saeed Vasebi, Stevens Institute of Technology
This policy analysis provides a broad view of health and safety impacts of traffic management strategies. Safety objectives of traffic management measures typically revolve around the crash reduction. Long term health threats caused by vehicle emissions are often ignored. In this policy paper, we provide an overall picture of health effects of air pollutants emissions, present a brief history of existing disjoint between environmental, health, and mobility objectives. We then provide two case studies showing how transportation operation and management measures could impact public health. In conclusion, we provide several insights useful for policymakers to consider health impacts of traffic management measures beyond what affects automobile crashes and climate change.
Modeling the Effects of Travel Activities, Physical Activity, and Built Environment Attributes on Subjective Well-being
Shivam Khaddar, University of British ColumbiaShow Abstract
Mahmudur Fatmi, University of British Columbia
Meghan Winters, Simon Fraser University
Transport studies have recently started focusing on the link between activity participation and subjective well-being. This study explores the relationship between subjective well-being and travel activities, physical activity, and built environment attributes. Individuals’ self-reported health condition is considered as the subjective well-being indicator. Using data from the Impacts of Bicycle Infrastructure in Mid-sized cities (IBIMS) survey of Kelowna, British Columbia, Canada, this study develops a latent segmentation-based random parameter logit (LSRPL) model. The LSRPL model is estimated for two segments capturing multi-dimensional heterogeneity by assuming a discrete distribution (i.e. inter-segment heterogeneity) and continuous distribution (i.e. intra-segment heterogeneity) of the parameters. Segment one is likely to include younger sub-urban dwellers residing in lower-income households; segment two includes older urban dwellers residing in higher-income households. The model results suggest that daily travel activity, physical activity, and built environment significantly influences health. For example, higher participation in travel and physical activity is positively associated with excellent health. The model confirms significant inter-segment heterogeneity. For instance, higher share of travel duration using car reduces the likelihood for excellent health in segment one. In contrast, a positive relationship is found in segment two. The model also confirms intra-segment heterogeneity. For example, higher share of commute duration is found to be negatively associated with good health in segment two. However, this variable shows higher heterogeneity in mean for land use mix index, which indicates that urban areas coupled with higher land use mix increases the likelihood for good health.
Incorporating Health-related Criteria for Project Scoring in Massachusetts
Katerina Deliali, National Technical University of Athens (NTUA)Show Abstract
Sarah Esenther, Yale School of Public Health
Christine Frisard, University of Massachusetts Medical Center
Karin Valentine Goins, University of Massachusetts Medical Center
Stephenie Lemon, University of Massachusetts Medical Center
Krystal Gordri Pollitt, Yale School of Public Health
Eleni Christofa (firstname.lastname@example.org), University of Massachusetts, Amherst
Transportation projects can affect health through multiple pathways, e.g., by degrading air quality or encouraging active transportation. There is a need to incorporate health considerations in transportation decision making to achieve health-related community goals. This paper presents highway project scoring criteria that allow for capturing the impact of transportation projects on health. These scoring criteria are organized in five groups: air quality, accessibility, equity, physical activity, and safety, to capture the multiple pathways that transportation interacts with health. The focus of this study was on updating the MassDOT Highway Division project scoresheet to incorporate health-related criteria. Evidence base, standards and data needs based on which each criterion is assessed, as well as limitations are summarized for each of the proposed criteria. The paper concludes with some general recommendations related to updating project scoring prioritization processes and current data needs to more effectively account for health outcomes in transportation decision making.
DISCLAIMER: All information shared in the TRB Annual Meeting Online Program is subject to change without notice. Changes, if necessary, will be updated in the Online Program and this page is the final authority on schedule information.