Our study has shown a significant improvement in the outcome of hospitalized motorcycle-related injured patients over the last 15 years. Although the anatomical injury severity of the head doubled, GCS on arrival improved, which indicates a better prehospital care. The mortality dropped from 6% to none. Furthermore, the incidence of motorcycle-related injuries dropped by almost 40%. This highlights the impact of the trauma system development and injury prevention in reducing mortality among hospitalized motorcycle-injured patients.
Globally, motorcycle-related deaths are quarter of all RTC deaths [1, 18–21]. It is expected to increase by 11% worldwide over the coming 10 years . The United Nations' global aim was to reduce road deaths by half over 2010 to 2020 . Interestingly, this was achieved in our setting [14, 24, 25] but not globally . The effect size and time of improvement vary between different countries [24, 25]. The effect size in our study is large compared with a multicenter study from Israel which showed reduced mortality by 43% . However, our study stemmed from a single hospital. These results can be attributed to improvements in the EMS prehospital care in the Abu Dhabi Emirate [14, 27], which was evidenced by the improved GCS of injured patients on arrival despite having more severe head injuries.
Over the last two decades, there have been tremendous improvements in injury prevention measures in the UAE. These included enforcement of safety regulations (such as helmet and speed law enforcement), use of safety devices (like helmet usage), installation of road speed cameras, penalties on speeding violations, and educational programs [1, 18 – 20, 28, 29] . This explains the reduction of the percentage of head injuries in the second period by 25% in our study. Although our city previously used motorcycles less than 4-wheel vehicles [6, 30], we have observed their recent increase as a cheap transportation and food delivery tool. Figure 2 compares motorized 2–3 wheelers mortality rate, standardized number of motorized 2–3 wheelers, and helmet law enforcement between UAE and other high-income countries [1, 18 – 20]. The motorcycle-related death rate increased sharply in the UAE from 2013 to 2016, which can not be explained by the minimum increase in the number of motorcycles used in the UAE (Figure 2). Modernization, improvement, and maturity of our trauma system in all its components contributed to the improved clinical outcome in the current study [16, 26, 31–33]. The increased severity of head injuries in our study may indicate low helmet compliance, low quality helmets, or improperly fastened helmets [7, 34, 35]. Collisions became less in high-speed streets/highways and increased in low-speed residential areas, which may explain this finding because riders may be less careful in using their helmets in these areas. Developing an injury prevention strategy to address the concerns regarding the quality of the helmets and collisions in the residential areas is important.
Limitations of the study
Our study has certain limitations. First, it is from a single hospital which limits its generalizability in all the UAE. Second, there was a gap in our registry from 2007 to 2014 due to a lack of research funding. Third, data on helmet use and clothing (including boots) on the incident and circumstance that led to the crash were missing in our trauma registry. We did not evaluate other important factors such as rider's behavior, riding experience, motorcycle safety technology (like Anti-Lock Brake systems), biomechanism of injury, and road characteristics to give us more insights into the cause of reduced mortality. Fourth, our study had a small sample size which may cause type II statistical error. Nevertheless, these patients represent the majority of those treated over seven years in a city of three quarter of a million population. Furthermore, this small sample enabled us to collect high-quality prospective accurate data with minimum missing data. Finally, our study didn't include patients treated at the Emergency Department who were discharged home, those with minor injuries who did not seek medical advice, and those who died on the streets; which has the risk of selection bias.