Childhood injury surveillance can be conducted at multiple sites in a low income setting like Karachi, Pakistan and yield valuable insights into the nature and external causes of injuries. The home is the most common place where unintentional childhood injuries occur from surveillance data; as also observed in other ED-based studies (Additional file 1) [3, 13, 19, 20]. Falls followed by dog bites and burns have been found to the most common mechanisms for these home injuries.
Community-based surveys on child injury prevention conducted by United Nations Children's Fund (UNICEF) and The Alliance for Safe Children (TASC) in six East and South Asian countries have shown that most of the non-fatal childhood injuries take place at home commonly among toddlers  One common hypothesis related to the high numbers of home injuries is that children spend significant amount of time at home especially in the younger ages; as a result they are exposed to a number of risks for home injury.
Our analysis showed that falls were the most common type of injury suffered by children at home accounting for more than half of the burden on EDs. This result is consistent with a recent study done in rural and suburban communities in Sindh and Balochistan provinces of Pakistan, which showed that about 51% of injuries in children between 1 and 8 years were attributed to falls . Work done in other Eastern Mediterranean countries such as Syria and Iran on home injuries has also shown falls to be commonest injury suffered by preschool children [9, 10, 21]. A study done in Turkey on non-fatal unintentional home injuries stated that the percentage of children between 0 and 4 years, 5 and 9 years and 10 and 14 years suffering from falls to be 35%, 71.5% and 30% respectively . Our study showed that the percentage of injury due to falls at home was increasing with the age, being highest in children between 5 and 11 years of age. The frequent causes of falls in our study were fall from steps/stairs followed by fall from bed.
In our pilot surveillance data dog bites is the second common home injury presenting to the EDs. This is consistent with some of the previous work and is very important locally [13, 23, 24]. Although there was no mortality due to dog-bite injury, many of these cases involved bites from stray dogs which are a common sight in Karachi due to lack of effective dog control measures. Dog bites have been reported as an important child health issue in Asia accounting for 56% of annual global deaths due to rabies, and represented a disease burden that is critical for both injury prevention and infectious disease (Rabies) control . It is also a burden where the health sector of Karachi has to work effectively at local levels with civic administration and local government to control the problem of stray dogs efficiently. A National Dog Bite and Rabies Surveillance system is operational in Pakistan , funded by World Health Organization, to collect data on cases of dog bites in Pakistan.
As shown in previous studies, burns were in the leading three causes of unintentional home injury in children [10, 15, 21, 22, 27]. The youngest children were most affected (age group of 1-4 years) as also shown in previous studies [12–14, 19] and the World report on child injury prevention . The inquisitive nature of young children combined with their inability to comprehend harmful risk factors, and dependence on adult supervision makes them highly vulnerable to injuries.
This nexus of risks is also true for the cases of road traffic injuries that had taken place right outside the home of the victim. Majority of these injuries had taken place when the child was playing on the street and was hit by a motorcycle. The lack of play grounds, safe play areas, and lack of separation of traffic from the pedestrian zone is an ever present risk, especially in crowded urban areas like Karachi.
Like previous studies, [13, 15, 28] our results show that males represented a higher proportion of injured children compared to females. This has been attributed to higher risk-taking behavior in boys compared to girls; but in this age group and in our setting might represent other cultural issues as well. For example, studies in Pakistan have revealed a strong 'son preference'  and this has been reported to allow boys greater and earlier independence Also, there is likelihood that in our society injured male children are brought to the hospitals for treatment while females are mostly taken care of at homes.
Majority of the children in our study had suffered from mild to moderate injuries. Our study also revealed that there is lack of social protection and health insurance in Pakistan and patients have to pay out of their pockets for the treatment. This has grave implications on the family, as a vicious cycle of poverty may begin especially in cases of severe morbidity requiring long-term treatment and care.
This study used data from a pilot child injury surveillance system and like other facility based date has potential sampling bias as the study was conducted in only four hospital EDs in a city with a population of over 15 million people. Moreover, these hospitals are likely to see mostly severe cases of injuries; many minor to moderate injuries are treated either at home or by local community clinics. It is also sometimes difficult to assess the intent of injury in ED settings; for example, falls and burns in the database were categorized as unintentional injuries however; these may be intentional in nature. Thirdly, there is a likelihood that the number of fatalities seen in this study is an underestimation as many cases of death following an injury are not brought to the hospital due to medico-legal complications.
Caretakers reported a very small percentage using measures to prevent their children's accessibility to hot liquids, hazardous material and medications, or using age-appropriate car-seats and seat-belts. It is essential that caretakers are provided injury prevention information and access to such measures to prevent and control the exposure of children to the hazards of home injuries.
In addition, some important policy and implementation issues related to home injury prevention and control can be highlighted through this study. Firstly, it is important that in Pakistan standards for constructing houses should be followed. In the absence of such standards variability in the height and width of the steps/stairs constructed within homes is common. There is also generally lack of safety gates/grills/locks for the stairs; some houses may not even have a stair banister. In Pakistan, there is a common to build multi-level houses that further increase the risk of falls among children. Secondly, the local government needs to take measures to control the stray dogs present in the city. Thirdly, traffic calming and speed reducing measures needs to be enforced in the residential areas and around parks and playgrounds so that children do not risk their lives while playing on the roads and streets.