The walking environment in Lima, Peru and pedestrian-motor vehicle collisions: an exploratory analysis

One-year impact of a multicomponent, street-level design intervention in Mexico City on pedestrian crashes: a quasi-experimental study

BACKGROUND

Mexico City implemented the Pasos Seguros programme to prevent pedestrian injuries and deaths at dangerous road intersections, which included street-level design changes, such as visible pedestrian crossings, sidewalk widening, refuge islands, lane reductions, pedestrian signals and adjustment of traffic light timing at these intersections. Few studies in low and middle-income countries (LMICs) have evaluated the effect of such interventions on pedestrian safety.

AIM

Assess the effectiveness of the Pasos Seguros programme at reducing total, injury and fatal pedestrian-motor vehicle crashes.

METHODS

Two-group quasi-experimental design. Monthly pedestrian crashes were obtained from the road incident database from Mexico City's Citizen Contact Center. The programme's effectiveness was evaluated by comparing 12 months preintervention to 12 months postintervention implementation using a negative binomial regression with random intercept with a difference-in-difference estimation. A qualitative comparative analysis was used to find the configuration of intersection characteristics and programme components associated with a decrease in pedestrian crashes.

RESULTS

Total pedestrian crashes were reduced by 21% (RR 0.79; 95% CI 0.62 to 0.99) after implementation of Pasos Seguros programme. This reduction was observed for pedestrian injury crashes (RR 0.79; 95% CI 0.62 to 1.00) and for fatal crashes (RR 0.61; 95% CI 0.13 to 2.92) although not statistically significant for the latter. A decrease in pedestrian crashes was found at the most complex intersections where more of the programme components was implemented.

CONCLUSION

The Pasos Seguros programme successfully decreased total and injury pedestrian crashes. Similar interventions may improve walking safety in other LMIC cities.

Leisure-Time and Transport-Related Physical Activity and the Risk of Mortality: The CRONICAS Cohort Study

BACKGROUND

The long-term health association of the leisure-time and transport-related physical activity domains of the International Physical Activity Questionnaire have not been established in Latin American settings. The authors aimed to quantify the 7-year all-cause mortality risk associated with levels of leisure-time and transport-related physical activity.

METHODS

Ongoing prospective cohort study conducted in 4 sites in Peru. People ≥35 years were randomly selected from the general population in each study site. The exposures were leisure-time and transport-related physical activity (International Physical Activity Questionnaire) at baseline. The outcome was all-cause mortality based on information retrieved from national records. Cox regression and sensitivity analyses were conducted.

RESULTS

There were 3601 people (mean age 55.8 y, 51.5% women). Greater levels of physical activity were associated with lower risk of all-cause mortality, an observation confirmed in sensitivity analyses. Compared with those with low levels of physical activity, leisure-time (≥500 metabolic equivalent of task minutes per week) and transport-related (500-1499 and ≥1500 metabolic equivalent of task minutes per week) physical activity were associated with 70% (95% confidence interval, 3%-90%), 43% (95% confidence interval, 18%-61%), and 42% (95% confidence interval, 8%-63%) lower all-cause mortality, respectively.

CONCLUSIONS

Greater levels of leisure-time and transport-related physical activity were associated with a strong reduction in the risk of all-cause mortality across different geographical sites.

The role of perceived pedestrian safety on designing safer built environments

OBJECTIVE

This study aimed to explore how pedestrians´ safety perception concerning the built environmental characteristics can assist in designing a safer built environment in an urban area in Mexico.

METHODS

The study involved two stages of data collection. In the first stage, a physical audit on selected urban roads was performed to assess the characteristics that may increase the perceived risk of a collision. An observational framework to evaluate the crossing areas, sidewalks and organizational factors was developed and used for data collection. In the second stage, an on-street questionnaire was applied to collect the perception of a group of 299 pedestrians about safety risks, road characteristics and their ideas for designing a safer built environment.

RESULTS

The physical road audit identified several features in the crossing areas and sidewalks, such as parked cars, movable and fixed obstacles, and lack of traffic signage, which may increase the risk of a pedestrian being involved in a collision. More than half of the road users who were interviewed either agree (27%) or strongly agree (29%) with the statement that crossing the roads in the area was safe. However, pedestrians also identified the following elements as detrimental for the safe use of roads: lack of traffic lights, too much traffic, lack of signs, and parked cars that obstruct visibility. Participants also raised issues beyond the physical infrastructure; for instance, a lack of respect shown by drivers to pedestrians. For designing a safer built environment, participants suggested several ideas highlighting pedestrianization of the road and widening the sidewalks, along with restricting parking of cars on the road.

CONCLUSIONS

This combination of findings provide valuable support for the premise that pedestrians may have a good sense of recognizing safety problems and the ability to see the solutions. Although the research was undertaken in the context of a municipality in Guadalajara, the role of pedestrian safety perception may be applicable in other urban settings in low and middle-income countries (LMICs), where local authorities are in charge of designing the road environment. This study highlights the relevance of including pedestrians' participation for a safer and human-centred design of our cities.

Bayesian approach to model pedestrian crashes at signalized intersections with measurement errors in exposure

This study intended to identify the potential factors contributing to the occurrence of pedestrian crashes at signalized intersections in a densely populated city, based on a comprehensive dataset of 898 pedestrian crashes at 262 signalized intersections during 2010-2012 in Hong Kong. The detailed geometric design, traffic characteristics, signal control, built environment, along with the vehicle and pedestrian volumes were elaborately collected. A Bayesian measurement errors model was introduced as an alternative method to explicitly account for the uncertainties in volume data. To highlight the role played by exposure, models with and without pedestrian volume were estimated and compared. The results indicated that the omission of pedestrian volume in pedestrian crash frequency models would lead to reduced goodness-of-fit, biased parameter estimates, and incorrect inferences. Our empirical analysis demonstrated the existence of moderate uncertainties in pedestrian and vehicle volumes. Six variables were found to have a significant association with the number of pedestrian crashes at signalized intersections. The number of crossing pedestrians, the number of passing vehicles, the presence of curb parking, and the presence of ground-floor shops were positively related with pedestrian crash frequency, whereas the presence of playgrounds near intersections had a negative effect on pedestrian crash occurrences. Specifically, the presence of exclusive pedestrian signals for all crosswalks was found to significantly reduce the risk of pedestrian crashes by 43%. The present study is expected to shed more light on a deeper understanding of the environmental determinants of pedestrian crashes.

Multilevel models for evaluating the risk of pedestrian-motor vehicle collisions at intersections and mid-blocks

Walking is a popular form of physical activity associated with clear health benefits. Promoting safe walking for pedestrians requires evaluating the risk of pedestrian-motor vehicle collisions at specific roadway locations in order to identify where road improvements and other interventions may be needed. The objective of this analysis was to estimate the risk of pedestrian collisions at intersections and mid-blocks in Seattle, WA. The study used 2007-2013 pedestrian-motor vehicle collision data from police reports and detailed characteristics of the microenvironment and macroenvironment at intersection and mid-block locations. The primary outcome was the number of pedestrian-motor vehicle collisions over time at each location (incident rate ratio [IRR] and 95% confidence interval [95% CI]). Multilevel mixed effects Poisson models accounted for correlation within and between locations and census blocks over time. Analysis accounted for pedestrian and vehicle activity (e.g., residential density and road classification). In the final multivariable model, intersections with 4 segments or 5 or more segments had higher pedestrian collision rates compared to mid-blocks. Non-residential roads had significantly higher rates than residential roads, with principal arterials having the highest collision rate. The pedestrian collision rate was higher by 9% per 10 feet of street width. Locations with traffic signals had twice the collision rate of locations without a signal and those with marked crosswalks also had a higher rate. Locations with a marked crosswalk also had higher risk of collision. Locations with a one-way road or those with signs encouraging motorists to cede the right-of-way to pedestrians had fewer pedestrian collisions. Collision rates were higher in locations that encourage greater pedestrian activity (more bus use, more fast food restaurants, higher employment, residential, and population densities). Locations with higher intersection density had a lower rate of collisions as did those in areas with higher residential property values. The novel spatiotemporal approach used that integrates road/crossing characteristics with surrounding neighborhood characteristics should help city agencies better identify high-risk locations for further study and analysis. Improving roads and making them safer for pedestrians achieves the public health goals of reducing pedestrian collisions and promoting physical activity.