An analysis of road traffic accidents using geographic information systems (GIS)

Road traffic accidents remain a daunting public health problem with an estimated 1.2 million people killed annually worldwide. Some 50 million persons are injured and incapacitated in road crashes around the globe every year. Developing countries, which have been experiencing an ever increasing number of road deaths and injuries, are the hardest hit, accounting for the vast majority. The implication is that road crashes place severe financial and human-resource constraints on developing countries where unmet needs compete for meagre resources available. This trend is likely to continue if no action is taken to carefully address the problem of road crashes, especially in the view of the increasing number of motor vehicles and comparative lack of safety culture and features in developing countries. The development of appropriate countermeasures needs to be based on sound analysis of crash events: their characteristics, contributing factors, surrounding environments and locations among others. Knowing where accidents occur leads to better accident analyses, better policing and development of the effective countermeasures. The evolving technologies in Geographic Information Systems (GIS) and Global Positioning Systems (GPS) are a gateway to this end. They enhance data (especially location referencing) accuracy and quality, and thus reliability of the results. In this study, Dr. Calvine Kayi uses both GIS and GPS in analyzing road accidents in Nairobi city and demonstrates how policy makers in developing countries can employ these techniques to support their road safety policy decisions.