Abstract
Pedestrian safety is a critical transportation and public health issue, with fatalities increasing substantially over the past decade. Given this trend, it is important to understand how to most effectively implement countermeasures that will help to prevent pedestrian crashes, injuries, and fatalities. The leading pedestrian interval (LPI) is one countermeasure that has been shown to improve pedestrian safety at signalized intersections. However, there is a lack of data-driven guidance on how LPIs affect turning vehicle–pedestrian conflict frequency and severity across different ranges of volumes and conditions. As such, this study analyzed field-collected video at crosswalks in Phoenix, AZ, to assess LPI safety performance before and after LPI implementation. Turning vehicle–pedestrian conflicts (measured using postencroachment time; PET) along with volumes and other characteristics were reduced from the video. Using these data, a series of negative binomial regression models were estimated to determine the association between hourly conflict frequency and volume, along with the impact of LPI presence. The results showed that LPI presence was associated with conflict reductions ranging from approximately 10% to 15% for all conflicts with PET ≤5.0 s and around 50% for severe conflicts. Finally, an ordered logit model was estimated to explore the effect of LPIs and other pedestrian and driver characteristics on conflict severity, and LPI presence demonstrated a significant reduction in the likelihood of severe conflicts. Ultimately, the results of this study could be useful for researchers and practitioners considering LPI implementation and could inform future iterations of LPI implementation guidelines.
Get full access to this article
View all access options for this article.