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Problem, research strategy, and findings: The monocentric development pattern in the Alonso–Mills–Muth model underpinned theoretical discussions of urban form in the 1960s and 1970s and truly dominated theory up to the point when Joel Garreau published Edge City: Life on the New Frontier in the early 1990s. Monocentric development patterns remain dominant to this day among smaller metropolitan areas in the United States. However, for larger metropolitan areas in the United States, regional transportation plans suggest a paradigm shift to a polycentric structure. We review 126 regional transportation plans in the United States and find that a hierarchy of centers connected by high-quality transit has become the dominant vision for most of them. The plan for Salt Lake City (UT), for example, strives for a multicentered region even though secondary centers are only beginning to emerge beyond a dominant downtown. Generally missing from regional transportation plans are quantitative criteria for designating and guiding centers: In no case are the quantitative criteria empirically based on proven transportation benefits. Here we investigate how the built environment characteristics of centers are associated with people's travel mode choices and vehicle use. We employ visual and exploratory approaches through a generalized additive model (GAM) to identify nonlinear relationships between travel outcomes and "D" variables (density, diversity, design, destination accessibility, and distance to transit) within centers. The model and plots help us recommend the built environment characteristics of centers. Takeaway for practice: The built environment thresholds and relevant tools provided here can enable planners to make informed decisions about future growth patterns, set realistic—yet visionary—goals, and improve the overall health of its residents and communities. We provide strategies and tools that planning agencies, such as metropolitan planning organizations, transit agencies, and municipalities, can adopt to channel developments into centers. [ABSTRACT FROM AUTHOR]

Guidelines for trip and parking generation in the United States come mainly from the Institute of Transportation Engineers (ITE). However, their trip and parking manuals focus on suburban locations with limited transit and pedestrian access. This study aims to determine how many fewer vehicle trips are generated and how much less parking demand is generated, by different housing types (single-family attached, single-family detached, and apartment and condo) and in different settings (from low density suburban environments to compact, mixed-use urban environments). Using household travel survey data from 30 diverse regions of the United States, we estimate a multilevel negative binomial model of vehicle trip generation and a multilevel Poisson model of vehicle ownership, vehicle trip generation and vehicle ownership being logically modelled as count variables. The models have the expected signs on their coefficients and have respectable explanatory power. Vehicle trip generation and vehicle ownership (and hence parking demand) decrease with the compactness of neighbourhood development, measured with a principal component that depends on activity density, land use diversity, percentage of four-way intersections, transit stop density and employment accessibility (after controlling for sociodemographic variables). The models capture the phenomena of 'trip degeneration' and 'car shedding' as development patterns become more compact. Reducing the number of required parking spaces, and vehicle trips for which mitigation is required, creates the potential for significant savings when developing urban projects. Guidelines are provided for using study results in transportation planning. [ABSTRACT FROM AUTHOR]

Guidelines for trip and parking generation in the United States come mainly from the Institute of Transportation Engineers (ITE). However, their trip and parking manuals focus on suburban locations with limited transit and pedestrian access. This study aims to determine how many fewer vehicle trips are generated at transit-oriented developments (TODs), and how much less parking is required at TODs, than ITE guidelines would suggest. Our sample of TODs is small, which limits our ability to generalize. However, the five cases selected for this study are more or less exemplary of the D variables, at least in comparison with US norms. They are characterized by land-use diversity and pedestrian-friendly designs. They minimize distance to transit, literally abutting transit stations. They have varying measures of destination accessibility to the rest of the region via transit. Three have progressive parking policies, which fall under the heading of demand management. Two have high residential densities, and one has a high intensity of commercial development. Simply put, our case study TODs create significantly less demand for parking and driving than do conventional suburban developments. With one exception, peak parking demand in these TODs is less than one half the parking supply guideline in the ITE Parking Generation manual. Also, with one exception, vehicle trip generation rates are about half or less of what is predicted in the ITE Trip Generation Manual . Automobile mode shares are as low as one quarter of all trips, with the remainder being mostly transit and walk trips. [ABSTRACT FROM AUTHOR]

This study pools household travel and built environment data from 15 diverse US regions to produce travel models with more external validity than any to date. It uses a large number of consistently defined built environmental variables to predict five household travel outcomes – car trips, walk trips, bike trips, transit trips and vehicle miles travelled (VMT). It employs multilevel modelling to account for the dependence of households in the same region on shared regional characteristics and estimates ‘hurdle’ models to account for the excess number of zero values in the distributions of dependent variables such as household transit trips. It tests built environment variables for three different buffer widths around household locations to see which scale best explains travel behaviour. The resulting models are appropriate for post-processing outputs of conventional travel demand models, and for sketch planning applications in traffic impact analysis, climate action planning and health impact assessment. [ABSTRACT FROM AUTHOR]

• 622 MXDs were identified in 31 metropolitan regions across the United States. • Well-designed MXDs have walk shares of more than 50 percent on internal trips. • MXDs with diverse activities and good transit service capture more internal trips. • Certain MXDs generate significant walk, bike, and transit shares on external trips. • A k-fold cross-validation supports the robustness of the analyses. This study aims to improve a previously-developed methodology for predicting the traffic impacts of mixed-use developments (MXDs). In 31 diverse metropolitan regions across the United States, we collected consistent regional household travel survey data and computed built environment characteristics—D variables—of MXDs. Multilevel modeling (MLM) was employed to predict the probability of trips captured internally within MXDs, walking on internal trips, and travel mode choice on external trips, by trip purpose. Larger, denser, mixed-use, and more walkable MXDs show a larger share of trips internally, compared with conventional suburban developments. Those MXDs with good access to transit, employment, and destinations also show higher levels of walking, biking, and transit shares on external trips, thus helping to reduce traffic impacts on the external road network. Perhaps the most impressive finding is that well-designed MXDs have walk shares of more than 50 percent on internal trips. A k-fold cross-validation supports the robustness of our analyses. [ABSTRACT FROM AUTHOR]

Transit-oriented development (TOD) has gained popularity worldwide as a sustainable form of urbanism by concentrating developments near a transit station so as to minimize auto-dependency and maximize ridership. Existing TOD studies, however, have limits in terms of small sample size and aggregate-level analysis. This study examines various travel outcomes – VMT, auto trips, transit trips, and walk trips – in rail-based station areas in eight U.S. metropolitan areas in order to understand the role of neighborhood built environment characteristics. Two-stage hurdle models handle excess zero values in trip count variables and multi-level models deal with three-level data structure – household within station areas within regions. The final models show that automobile use is associated with land-use diversity and street network design of a station area; transit use is strongly related to transit availability and land-use diversity; and walking is related to transit availability, land-use diversity, and street network design. The weakest influence among station-area environment factors is density. In sum, a TOD, a station area having a dense, mixed-use, walkable, and transit-friendly environment, motivates residents to walk more and take transit more while driving less. [ABSTRACT FROM AUTHOR]

Importance: Motor aphasia is common among patients with stroke. Acupuncture is recommended as an alternative therapy for poststroke aphasia, but its efficacy remains uncertain., Objective: To investigate the effects of acupuncture on language function, neurological function, and quality of life in patients with poststroke motor aphasia., Design, Setting, and Participants: This multicenter, sham-controlled, randomized clinical trial was conducted in 3 tertiary hospitals in China from October 21, 2019, to November 13, 2021. Adult patients with poststroke motor aphasia were enrolled. Data analysis was performed from February to April 2023., Interventions: Eligible participants were randomly allocated (1:1) to manual acupuncture (MA) or sham acupuncture (SA) groups. Both groups underwent language training and conventional treatments., Main Outcomes and Measures: The primary outcomes were the aphasia quotient (AQ) of the Western Aphasia Battery (WAB) and scores on the Chinese Functional Communication Profile (CFCP) at 6 weeks. Secondary outcomes included WAB subitems, Boston Diagnostic Aphasia Examination, National Institutes of Health Stroke Scale, Stroke-Specific Quality of Life Scale, Stroke and Aphasia Quality of Life Scale-39, and Health Scale of Traditional Chinese Medicine scores at 6 weeks and 6 months after onset. All statistical analyses were performed according to the intention-to-treat principle., Results: Among 252 randomized patients (198 men [78.6%]; mean [SD] age, 60.7 [7.5] years), 231 were included in the modified intention-to-treat analysis (115 in the MA group and 116 in the SA group). Compared with the SA group, the MA group had significant increases in AQ (difference, 7.99 points; 95% CI, 3.42-12.55 points; P = .001) and CFCP (difference, 23.51 points; 95% CI, 11.10-35.93 points; P < .001) scores at week 6 and showed significant improvements in AQ (difference, 10.34; 95% CI, 5.75-14.93; P < .001) and CFCP (difference, 27.43; 95% CI, 14.75-40.10; P < .001) scores at the end of follow-up., Conclusions and Relevance: In this randomized clinical trial, patients with poststroke motor aphasia who received 6 weeks of MA compared with those who received SA demonstrated statistically significant improvements in language function, quality of life, and neurological impairment from week 6 of treatment to the end of follow-up at 6 months after onset., Trial Registration: Chinese Clinical Trial Registry: ChiCTR1900026740.