Assessing the Impact of Road Lighting on Reducing Severe Nighttime Crashes: A Case-control Study on Rural Roads in Khorasan Razavi Province, Iran

The increasing rate of nighttime road crashes, despite lower traffic volumes, underscores the need for effective safety measures. Road lighting has proven to be a key countermeasure for reducing severe nighttime crashes; however, its implementation is costly and time-consuming, necessitating a thorough evaluation. This study employs the case-control method, an epidemiological approach suitable for rare events like crashes, to assess the impact of road lighting on severe nighttime crashes on rural roads in Iran. Three approaches—simple, stratified, and matched—yield Crash Modification Factors of ۰.۳۹, ۰.۴۰, and ۰.۵۳, respectively, indicating significant reductions in crashes. These findings highlight the effectiveness of road lighting in enhancing road safety. In addition, the reliability of the estimated Crash Modification Factor was evaluated using the star quality rating approach, and the results achieved a ۴-star rating out of ۵, indicating a relatively high level of confidence in the study findings. By providing multiple CMF estimates with a high level of reliability, this study supports evidence-based decisions, aiding transportation authorities in optimizing resource allocation for safety interventions and contributing valuable insights to road safety literature.

کلیدواژه ها:

Crash Modification Factor ، Road Lighting ، Case-control Study ، Safety Evaluation ، Star Quality Rating