Single Entry Communities Increase Trip Distance and May Overestimate Neighborhood Walkability

Background: Neighborhood walkability is being promoted as an important factor in public health efforts to decrease rates of physical inactivity. Single entry communities (SEC), communities with only 1 entrance/exit, may result in an over estimation of walkability. This design makes direct walking routes outside the community nearly impossible and results in increased trip distance. The purpose of this study was to determine if accounting for SECs resulted in a significant difference in street connectivity. Methods: Twenty geographically different Las Vegas neighborhoods were chosen and the number of true intersections measured in ArcGIS. Neighborhoods were then assessed for the presence of SECs using google maps, ArcGIS land imagery, and field observation. Intersections inside SECs were removed. A paired t test was used to assess the mean difference of intersection density before and after adjustment. Results: There was a statistically significant decrease in the number of true intersections after the adjustment (before mean = 57.8; after mean = 45.7). The eta squared statistic indicates a large effect size (0.3). Conclusions: Single entry communities result in an over estimation of street connectivity. If SECs are not accounted for, trip distances will be underestimated and public health efforts to promote walking through walkable neighborhoods may prove less effective.