National and metropolitan trends in public transit use, transit-related walking, and ridesharing between 2009 and 2017.

Walking is a common form of physical activity and is the most frequent way to access public transit. On-going changes in the US transportation system are occurring, notably increases in smartphone application-based ridesharing. The goal of this research is to assess whether increasing use of ridesharing was associated with a change in transit-related walking. This is important to both public health and transportation, as it can inform changes in active transportation which promotes both physical activity and transit use. We examined the association between change in transit use, transit-related walking, and ridesharing nationally and for selected metropolitan areas using the 2009 and 2017 National Household Travel Survey (≥18 years; n = 263,572 and n = 230,592, respectively). Analyses were conducted in 2019. Covariates included sex, age, race/ethnicity, education, employment, work from home, household size, number of vehicles, population density, Census region, metro area size and heavy rail transit category and season. The national prevalence of transit use in the past month in 2009 was 16.9% (95% CI: 16.4%-17.4%) and in 2017 was 16.1% (15.6%-16.6%), a significant decrease (p < 0.02). The prevalence of daily transit-related walking in 2009 was 4.2% (4.0%-4.4%) and in 2017 was 4.4% (4.2%-4.6%; p = 0.22). The prevalence of daily taxi use in 2009 was 0.5% (0.4%-0.6%) and taxi/rideshare in 2017 was 1.1% (1.0%-1.2%), a significant increase (p < 0.0001). The relationships remained after covariate adjustment. Finally, there was not a significant change in transit-related walking or interaction between year and taxi/rideshare use after additional adjustment for taxi/rideshare. Changes in transit-related walking in metros were largely not significant, whereas increases in taxi/rideshare were largely significant. Results suggest that increased use of ridesharing may not be linked with changes in transit-related walking. Continued surveillance of travel mode prevalence is required to track potential reductions in population-level physical activity with technology-related changes in travel.