As Smart Growth America releases its best practices to evaluate the success of Complete Streets efforts, we at Salud America! want to draw attention to how transportation needs and barriers have been conceptualized.
This post was written by Amanda Merck from Salud America!
Across the fields of urban planning, public health, and health care, transportation needs and barriers have been poorly conceptualized and poorly operationalized (i.e., defined and measured). This is played out in practice through things such as the application of Complete Streets policies.
We need urban planners to expand their understanding of how transportation impacts health and quality of life and push for better data collection on whether Complete Streets and transportation investments and initiatives are meeting the needs of community members.
Why Should Urban Planning Stakeholders Care About Transportation as a Social Determinant of Health?
Health is influenced by genetics and medical care. But health is primarily shaped by “the conditions in which people are born, grow, work, live, and age, and the wider set of forces and systems shaping the conditions of daily life,” according to the World Health Organization. These non-medical factors are known as social determinants of health (SDoH).
“Neighborhood and Built Environment” is one of the five SDoH domains making it relevant to urban planning practitioners, scholars, and policymakers. The problem in the U.S. is that neighborhoods were not created equal. Across the U.S., segregated and disconnected neighborhoods are overburdened by the concentration of poverty, underperforming schools, low food access, and unsafe, unreliable, unaffordable, and inadequate transportation. These adverse neighborhood and built environment conditions contribute to inequities in health outcomes, as well as inequities in social and economic outcomes, which exacerbate inequities in health.
How is Transportation as a SDoH Conceptualized and Operationalized?
There is no widely agreed upon concept of transportation needs/barriers, thus no widely agreed upon methods to measure transportation needs/barriers. Transportation needs/barriers are often operationalized in terms of vehicle ownership, peak travel time reliability for commuters in single-occupancy vehicles, proximity to transit, or satisfaction with transportation. These metrics fail to capture what is perhaps the most basic of all transportation performance questions, is public investment in transportation improving quality of life?
Vehicle ownership, for example, is often only measured in terms of number of household vehicles – with no regard for the number of adults in the household and the financial burdens of operating and maintaining a vehicle. Similarly, proximity to transit is often only measured in terms of distance to a transit route or transit stop – with no regard for the quality of transit service and the burdensome tradeoffs associated with dependence on transit, particularly in cities where transit is operated as a social safety net for disadvantaged populations, marked by infrequent service that is limited on evenings and weekends.
Transportation needs/barriers have yet to be conceptualized in terms of tradeoffs people are making to adapt to unsafe, unreliable, unaffordable, and inadequate transportation. They miss when people forego trips to essential destinations and skip spending on essentials.
While there has been a lot of effort to understand needs and barriers related to housing instability and low food access as social risk factors that contribute to health-related social need, there has been little effort to understand needs and barriers related to inadequate transportation. For example, the concepts of low food access and food insecurity have been established for over two decades, but no similar concept covers inadequate transportation or transportation insecurity.
National data on food insecurity have been collected by the U.S. Department of Agriculture (USDA) annually since 1995. Contrast this with transportation. There is no widely established concept of limited or uncertain access to adequate transportation that results in households being unable to meet their transportation needs. The U.S. Department of Transportation (USDOT) does not collect annual data on if households are able to meet their transportation needs.
Below are brief summaries of some of the different ways inadequate transportation has been conceptualized and operationalized.
National Household Travel Survey. The National Household Travel Survey (NHTS), the only national source of personal travel data collected by USDOT, focuses on travel behavior. It does not measure if people are able to meet their transportation needs.
Unlike the previous NHTS in 2017, the most recent NHTS in 2022 asked people to share reasons why they didn’t travel (i.e., took zero trips on the day of the survey) and why they traveled less (i.e., took fewer trips in the past 30 days). However, the questions are unable to capture if and why people skipped trips that they needed to take.
Transportation Insecurity. A new set of measures was recently developed and validated by sociology scholars to assess a concept they coined as transportation insecurity. The tool assesses the experiences of inadequate transportation (e.g., being late, skipping trips, and worrying). But it does not assess sources of inadequate transportation (e.g., unreliable vehicle, insufficient transit, and transportation cost burden).
Measures of transportation problems like these are a good start, but unable to inform stakeholders about the source of the transportation problem, thus are unable to inform stakeholders about needed interventions.
Social Need/Risk Screening Tools. Because SDoH are significantly associated with health outcomes, there are a growing number of initiatives to screen for and address social risk/needs within the health care system, such as efforts in Texas, Pennsylvania, and community health centers across the country. SDoH screening can help shed light on transportation problems. For instance, one study found unreliable transportation had the largest significant association with increased hospital stays and emergency department visits compared to other health-related social needs (i.e., financial strain, housing insecurity, poor housing quality, food insecurity, utility insecurity, and loneliness).
Other Travel Behavior Surveys. Local transportation needs assessments often focus on travel behavior, satisfaction with transit, and other measures of comfort. They rarely measure needs and barriers.
Regarding transit specifically, customer satisfaction fails to represent the quality of transit service provided. While satisfaction does vary in a plausible way and is affected by changes in transit service, such as access to bus stops and bus travel time, there is no evidence that satisfaction is fully representative of quality or of people’s ability to meet their transportation needs.
Transportation Performance. Even more progressive transportation policies and practices, like Complete Streets and performance-based planning and programming, lack the methodology to measure if transportation investment is reducing barriers and meeting people’s transportation needs.
Performance-based planning, for example, often focuses on reducing vehicle delay. This results in the investment of hundreds of millions of dollars in U.S. communities to shave a few minutes off peak vehicle commute time, despite that transit commute times are often nearly double vehicle commute times.
While Complete Streets efforts focus on improving safety, reducing vehicle travel, and increasing physical activity, they often do so without assessing if people can meet their transportation needs without burdensome tradeoffs.
What Do We Do Next?
Without information about the sources, symptoms, and consequences of inadequate transportation, planners and decision-makers do not know which transportation investments or initiatives are reducing transportation barriers and meeting people’s transportation needs. Read the full version of this Salud America! blog post, which includes an example of and recommendations to use a theory of change logic model to more comprehensively conceptualize transportation as a SDoH, particularly in terms of Complete Streets.
Only when people are able to meet their transportation needs without burdensome tradeoffs can our streets be truly complete.