Motorcycle crash injury severity factors in Pakistan: Towards reliable traffic safety policies

In low- and middle-income countries like Pakistan, motorcycle use has grown rapidly due to urban expansion and limited transport options. While motorcycles offer an affordable means of travel, the increase in their number is accompanied by a rise in serious and fatal crashes, creating significant road safety and public health concerns. Although global research has explored motorcycle safety, there is a lack of region-specific studies in Pakistan, particularly on how roadway geometric features affect crash severity. This study aims to address that gap by examining factors that influence injury severity in motorcycle crashes, with a focus on road geometry, as well as temporal, weather, and crash-related conditions. A random parameters model, accounting for heterogeneity in means and variances, is utilized to analyze motorcycle crash data comprising 18,115 observations collected in Rawalpindi, Pakistan, between 1 January 2020 to 31 July 2023. Model assessment for heterogeneity in the means and variances identifies four significant variables, i.e., constant, nighttime, rainy weather, and intersection presence, which yield statistically significant random parameters, reflecting heterogeneities in effects. The findings indicate that temporal and weather attributes (e.g., COVID-19 effect, summer and winter seasons, nighttime, peak traffic hours, and rainy weather) significantly increase the risk of severe injuries in motorcycle crashes. In addition, crash-related factors (e.g., speeding, clothes stuck in motorcycle tires, and collisions with pedestrians, motorized rickshaws, other motorcycles, and heavy vehicles) were identified as major contributors to the severity of injuries. Moreover, road geometric features (e.g., primary roads, fewer lanes, horizontal and vertical curves, and narrow shoulders) were also strongly associated with more severe crash outcomes. Based on these findings, several targeted interventions, including awareness campaigns, enforcement of speed limits, management of mixed traffic, and enhancement of road conditions and geometries, are recommended to reduce motorcycle crashes and enhancing overall transportation safety.