Exploring the risk factors associated with the size and severity of roadway crashes in Riyadh

• We examine the main factors affecting the severity and size of traffic crashes in Riyadh.
• Crash reason, damages in public property, day of the week, crash location, and point of collision were the significant variables affecting the severity of crashes.
• Road factor was the most significant factor affecting the size of crash followed by the driver and environment factors.

IntroductionRecently, growing concern has been shifting toward the necessity of improving traffic safety in the Kingdom of Saudi Arabia (KSA). KSA has a unique traffic safety problem in that: (a) it can be classified as a developed country in terms of the magnitude and quality of the roadway networks available and its compatibility with international standards; however, (b) it can also be considered a developing country as the rate of increase in the number of road crashes is substantial compared with relevant figures of other developing countries and other countries of the Gulf region. Hence, more research efforts are still needed.ObjectivesThis paper examines the nature and causes of fatal and serious traffic crashes in KSA so that solutions and/or future studies can be suggested.MethodData from 11,545 reported fatal and injury traffic crashes that occurred in Riyadh (the capital of KSA) during the period 2004–2011 were analyzed by alternative and complementary methods. A logistic regression model was estimated and the results revealed that crash reason (speeding), damages in public property, day of the week, crash location (non-intersection location), and point of collision (head-on) were the significant variables affecting the binary target variable (fatal and non-fatal crashes). Additionally, the structural equation modeling approach was developed to identify and quantify the impacts of significant variables influencing crash size (e.g., no. of injuries, no. of vehicles involved in the crash). Crash size is one of the important indices that measure the level of safety of transportation facilities.ResultsThe results showed that road factor was the most significant factor affecting the size of the crash followed by the driver and environment factors.Impact on IndustryConsidering the results of this study, practical suggestions on how to improve traffic safety in KSA are also presented and discussed.