Our results confirmed that the most common age of pediatric injury - related mortality was 1 - 4 years and it was more common in boys. Traffic accident was the most prevalent cause and accidental injury was the most common manner of death. Most decedents passed away at the scene and the majority of cases died in the first 6 hours following the injury.
In our study, the pediatric crude mortality rate was 21.5 per 100000 population in each year for children younger than 15 years of age. However, Naghavi et al., reported a pediatric injury - related mortality rate of 35 per 100000 population in their study for the same age group, which was based on Iran’s death registration data of 2005 (
2). Although this difference may be explained in part by measuring crude mortality rate in different populations, it may also indicate the effect of the health system’s effort to reduce the injury - related deaths in Shiraz during a 10 - year - period.
In this study, children with 1 - 4 years of age had the highest injury - related mortality. This is similar to a report from northern Iran with the highest rate of trauma (43%) in children under 5 years (
17). Also, studies from Sub - Saharan Africa, Japan, and the United Arab Emirates report a high rate of injury-related mortality in 1 - 4 year old children (
4,
18,
19). Absence or neglect of the caregiver and insufficient knowledge, curiosity, and special physiology of children younger than 5 years of age might have a role in higher injury - related mortality of this age group (
1,
18).
The lowest proportion of injury - related death in infants is in concordance with studies from Qatar and China (
6,
20,
21). This finding may be partly due to inability of an infant with less than 1 year of age to walk and to have a dangerous interaction with the environment.
Consistent with other reports from Iran (
2), Qatar (
6), India (
22), and South Africa (
5), traffic accident was the main cause of mortality in all age groups in our study. Another study in Eastern Mediterranean region (EMR), including Iran, revealed that the leading cause of death due to unintentional injuries among children was road traffic injuries (
23). According to the WHO Global Burden of Disease project, road traffic deaths in Africa and EMR are high and children’s deaths in these events were estimated 21%. Also, almost 30% of all injury related deaths were among children. It is predicted that by the year 2030, road traffic injuries will be the fifth leading cause of deaths worldwide (
1). Non - standard safety designs of vehicles and roads (
23) and failure to take safety measures (
16) are two important reasons for the high rate of traffic accidents. Thus, traffic accident morbidity and mortality imposes a heavy burden on the public health system globally, especially in developing countries like Iran, and requires prioritization (
16,
23,
24).
In our study, mortality due to traffic accidents was more common in 1 - 4 years age group. This might partly be due to insufficient knowledge or the failure of caregivers of younger children to take safety measures such as using the child safety seat in the car in Iran as a developing country (
16). On the other hand, small children are too short to be visualized by drivers as pedestrians (
25) and their sensory facilities (visual and auditory) are not fully developed (
1). Also, children are in a growing state and their relative softness makes them physically more vulnerable to the impact of injury as compared to adults (
1).
In the present study, most cases of suffocation were in the age range of 10 - 18 years. This is similar to reports from South Africa, San Diego, and Lorestan province of Iran (
3,
5,
10). This is possibly due to enough knowledge and ability of such children to perform hanging. On the contrary, our results showed that all cases of aspiration were accidental in infants and children up to five years. This is in concordance with reports from Brazil and Japan (
4,
26). Also, airway obstruction was the most common cause of injury - related mortality in a report from Tehran (
27). These findings are usually due to inadequate knowledge and the curiosity of these small children. Also, it can be explained in part by the tendency of children at this age to put different objects into their mouths (
28) and inability to chew foods adequately that increases the risk of aspiration (
29).
Deceased cases due to electrical injury, falling down, burns, and drowning were also more common in smaller children similar to reports from Lorestan and South Africa (
5,
10). The exploratory nature of children with less than 5 years of age (
30) and their lack of awareness to avoid high - risk behaviors are probably the explanation for these findings (
31).
Similar to our results, reports from Brazil and Lorestan showed that children older than 15 years had the highest mortality due to firearms (
10,
26). This may be explained by higher rates of retaliatory attitudes (
32) and easier access to firearms (
33) in children of this age category. Therefore, educating the families regarding safe storage of the firearms is very important.
The greatest mortality rate secondary to poisoning was observed in children aged 15 - 18 years followed by 1 - 4 years, which is similar to the studies in Lorestan and South Africa (
5,
10). In another recent study from Shiraz, children aged 13 - 18 years had the highest hospital admissions due to poisoning (
34). Although most of the deaths secondary to poisoning, especially in the younger children, are accidental (
35), the higher rate of deaths due to poisoning in the 15 - 18 years age group is probably due to increased number of suicidal attempts in this age group (
36). Thus, educating the parents regarding safe storage of toxic substances and medications as well as taking care of teenager’s mental health should be taken into account as one of the priorities of the health system.
A male predominance was observed in all age categories regarding pediatric mortality in this study. These results are in accordance with other reports from Iran, Japan, India, San Diego, and Eastern Mediterranean Region (
2-
4,
22,
37). Curiosity and the impulsive nature of boys compared with girls can justify these findings (
3). However, it is astonishing that girls had a higher number of firearm - related mortality than boys, which might have happened following sexual abuse. This result is in contrast with other reports from the United States that show male predominance regarding firearm - related mortality (
38,
39). Easy access to firearms (
33) and presence of male with ethnic minorities who are at greater risk for firearm assault in the United States (
38) may contribute to this gender discrepancy.
Most cases in this report were deceased in an accidental manner. This statement is in accordance with a study conducted in Tehran on childhood injuries (
40) and the studies performed in San Diego (
3) and South Africa (
5). In our study, the second most common manner of death was suicide followed by homicide, which did not coincide with the last two studies. Intentional injuries including homicide and suicide accounted for 24.2% and 9.4% of deaths in San Diego (
3) and 14% and 7% of deaths in South Africa (
5) reports, respectively. The higher rate of homicidal - related mortality in these 2 studies is probably due to easier access to firearms, the most common means of firearm, in the United States and South Africa compared with Iran (
3,
5). Most suicidal deaths in our study were performed by hanging, as previous studies in Shiraz (
41) and in the South Africa report (
5). Although these results show that most cases of injury-related deaths are due to preventable accidents, an increased proportion of pediatric suicidal deaths in Shiraz is an important public health problem that should be dealt with properly.
In most previous reports like our study, the majority of cases died at the scene (
3,
26) in contrast to the Tehran study on children less than 5 years of age that most cases died at the hospital (
27). This difference might be due to a lower age range of the Tehran study population with a lower risk of facing highly fatal injuries that kill the subject quickly at the scene. Also, in accordance with our finding, in the Brazil and San Diego reports, most cases died within the first 24 hours (
3,
26). This might be due to the severity of events or it can be due to more vulnerability of children against injuries.
The main limitation to our study was its retrospective design. Also, lack of some information in Shiraz Legal Medicine Organization Registry database including a small number of families that may have buried their dead child directly without referring to Legal Medicine Organization and also occasional death with uncertain cause in the hospitals with no referral to Legal Medicine Organization. Therefore, a minor gap might be present in our result compared with the actual data. Further studies with prospective design that address these limitations are recommended.
In conclusion, pediatric and adolescent death imposes a high economical and emotional burden on society. Pediatric injury - related mortality in Shiraz was more common in boys and in 1 - 4 years age group. Traffic accident was the most prevalent cause and accident was the most prevalent manner of death. Most of the injury - related mortalities are due to preventable injuries. Therefore, preventive measures such as educating the caregivers and using protective devices such as seat belt, helmet, and child safety seat are highly effective and recommended. Although the clinical management of trauma patients has been improved in recent decades, better concordance between systems involved in trauma prevention and management is necessary to reduce the burden of disease. Also, injury prevention should be considered as one of the priorities of the health system in order to minimize the rate of injuries and injury-related mortality with appropriate plans and actions.