Aim: Road Traffic Crashes (RTCs) are among the most important causes of trauma and death. This study aimed to investigate the environmental- and human-related risk factors of RTC mortality and to evaluate the quality of hospital care provided for traffic crash patients in East Azerbaijan Province in 2018 based on expected mortality estimations using the Injury Severity Score (ISS). Subject and methods: We evaluated 1000 medical records of trauma patients at referral hospitals. Demographic and clinical characteristics of trauma patients and hospital care quality were collected. Multiple logistic regression analysis was carried out to estimate adjusted odds ratios with 95% confidence interval for crash mortality. Results: The case-fatality ratio was 72 per 1000 patients. In the final analysis, a poor level of education increased the likelihood of mortality by 3.77 times (P< 0.05). Pedestrians, motorcyclists, and passengers had a higher likelihood of death compared to car drivers (P< 0.05). Nighttime crashes and injury severity score (ISS) significantly increased the likelihood of mortality by 3.7 and 2.26 times, respectively (P< 0.05). Our analysis revealed that a one-unit increase in revised trauma score (RTS) increased the likelihood of crash mortality by an average of 15%. Observed and expected death were 72 and 67, respectively. Conclusions: We found that the level of education, the traffic role of an injured person, the crash site, lighting status, length of time to arrive at the first hospital, head trauma, ISS, and RTS scores were associated with crash mortality. Additionally, the quality of hospital care provided to trauma patients needs to be improved.