Impact evaluation of camera enforcement for traffic violations in Cali, Colombia, 2008-2014.

INTRODUCTION: Cameras for detecting traffic violations have been used as a measure to improve road safety in different countries around the world. In Cali, Colombia, fixed cameras were installed in March 2012 on a number of roads and intersections. All camera devices are capable of detecting simultaneously the following traffic violations: driving over the speed limit, running a red light or stop sign, violation of the traffic ban schedule, and blocking the pedestrian crosswalk. OBJECTIVE: To evaluate the impact of camera enforcement of traffic violations in Cali, Colombia. METHODS: A quasi-experimental difference-in-differences study with before and after measurements and a comparison group was conducted. We observed 38 intervention areas and 50 comparison areas (250 m radius), during 42 months before and 34 months after the installation of cameras. Effects were estimated with mixed negative binomial regression models. RESULTS: In intervention areas, after 12 months, there was a reduction of 19.2% of all crashes and a 24.7% reduction of injury and fatal crashes. In comparison areas, this reduction was 15.0% for all crashes and 20.1% for injury and fatal crashes. After adjusted comparisons, intervention sites outperformed comparison sites with an additional yearly reduction of 5.3% (p = 0.045) for all crashes. CONCLUSIONS: The use of cameras for detecting traffic violations seems to have a positive effect on the reduction of crashes in intervention areas. A beneficial spillover effect was found as well in comparison areas; but more evaluations are needed.

First motorcycle-exclusive lane (Motovia) in Colombia: perceptions of users in Cali, 2012-2013.

This study's goal was to evaluate the pilot exclusive lane for motorcycles (Motovía) in Cali, Colombia, from the perception of its users in 2012-2013. A cross-sectional study using roadside surveys plus a qualitative component of individual semi-structured interviews was carried out. Road users' perceptions were investigated before and after implementation of lane dividers (LD) and were compared with other roads in the city. Perceptions were compared using chi-square tests. In the study, 293 motorcyclists, 111 cyclists, and 115 automobile drivers were interviewed. Following the installation of the LD, the majority of motorcyclists and cyclists reported that LD made easier the driving maneuvers and decreased travel time, in contrast to perceptions of automobile drivers (p < 0.001). For most motorcyclists, the Motovia was considered as safe and effective, approving its continuity and replication. Half of automobile drivers and cyclists did not approve the installation of the Motovia due to travel time (drivers) and security issues (cyclists). Motovia is an option to enhance motorcyclists' safety on the road. It must, however, offer clear circulation alternatives for automobile drivers. According to users' perception, it is not safe for bicycles and other human-powered vehicles to share lanes with motorcycles. Further research about vulnerable road users' infrastructure is required.

Driving under the influence of alcohol in Cali, Colombia: prevalence and consumption patterns, 2013.

This study's goal was to establish the prevalence of driving under the influence of alcohol (DUI) and alcohol consumption patterns among drivers in Cali, Colombia, in 2013. A cross-sectional study based on a roadside survey using a stratified and multi-stage sampling design was developed. Thirty-two sites were chosen randomly for the selection of drivers who were then tested for blood alcohol concentration (BAC) and asked to participate in the survey. The prevalence of DUI was 0.88% (95% confidence intervals [95% CI] 0.26%-1.49%) with a lower prevalence when BAC was increasing. In addition, a higher prevalence was found during non-typical checkpoint hours (1.28, 95% CI -0.001%-0.03%). The overall prevalence is considered high, given the low alcohol consumption and vehicles per capita. Prevention measures are needed to reduce DUI during non-typical checkpoints and ongoing studies are required to monitor the trends and enable the assessment of interventions.