Chapter 3: Injury Prevention

Injury is a leading cause of death, disability and health care costs worldwide. The Global Burden of Disease Study, which creates a unique framework by which to assess national trends in all-cause and cause-specific mortality and morbidity, has shed light on the burden of injury relative to the denominator of all morbidity and mortality.¹ This research and other prominent publications have been instrumental in moving injury to a level of recognition commensurate with its level of disease burden. Injury has begun to gain recognition as a prominent public health issue as thought leaders, researchers, and clinicians are vigorously studying the issues within a framework by which prevention efforts, trauma systems, and advocacy strategies can be developed and maintained.

Approximately 5.8 million people die globally from injury-related causes. As a consequence of inadequate surveillance in many parts of the world, that number is likely to be much higher. Injury is responsible for more deaths worldwide than HIV, tuberculosis and malaria combined. The impact is projected to increase over time relative to other leading causes of death (Table 3-1).² Greater than 90% of injury deaths occur in low and middle income countries, and, within individual countries, vulnerable populations tend to be of lower socioeconomic status. This further hampers the progress of already struggling communities.

In several ways the burden and demographics of injury in the United States provide an example of the patterns seen worldwide; that is, injury is most prevalent in communities of lower socioeconomic status, rates of injury are higher in men than women, and young people are disproportionately affected by injury. According to the Centers of Disease Control and Prevention, unintentional injury remained the leading cause of death in the United States from age 1 to 44 years in 2013. Unintentional injury, suicide, and homicide are the first, second and third leading causes of death in the age group 15–34 years, respectively. Homicide remains the leading cause of death in the United States in African-Americans 15–34 years old and second in Hispanics of the same age. Unintentional injury is the third leading cause of death of all Americans with motor vehicle crashes and falls, particularly in the elderly, having a significant impact.³

Death is the tip of the iceberg in understanding the impact of injury.² In order to understand its magnitude, it is important to look at disability, along with the age at which a person is killed or injured. Calculations of disability adjusted life years (DALY), or the sum of years of life lost due to premature death and the years of productive life lost due to disability, are performed using a standard disability weight for each particular type of injury such as amputation, paralysis, post-traumatic stress disorder, etc.⁴ Although the DALY calculation has been criticized in its global applicability, it highlights the impact of injury on the younger portion of the population who are either very early in their lives or in the middle of their years of economic productivity which imposes a tremendous societal cost.

To round out the picture of the impact of injury, cost should be taken into consideration. Direct health care costs can be calculated and modeled. Indirect costs, including the psychological impact, loss of productivity affecting entire families, and societal costs of injury are more difficult to calculate, but we have a growing understanding of their magnitude. Road traffic injuries alone cost most countries 1–2% of their gross national product.^5,6 A study in Ghana found that 25% of households affected by injury had a decline in their food consumption.⁷ The recent release of the Lancet Commission on Global Surgery included a discussion on catastrophic expenditure from surgical disease, defined as out of pocket payment for treatment services exceeding 10% of annual household income. This is a critical issue in surgical care, and injury is a leading part of that. In the United States, hospitalization alone for injury exceeded $80 billion in direct costs and $150 billion in lost wages in 2010.⁸

A chapter focused on Injury Prevention cannot properly be discussed without first understanding injury’s influence on health and wealth. Understanding the global, national, and local impact of injury by mechanism and demographics is a critical start to launching into a strategy of targeted injury prevention appropriate for a particular location and population. A detailed investigation into these components along with understanding risk factors and protective factors not only allows us to understand the target population for prevention efforts, but can also be the cornerstone of creating a strategic plan for appropriate measures in education, engineering, and enforcement. In addition, understanding the public health impact of injury allows targeted advocacy for legislation and financial resources necessary to initiate many prevention plans. Understanding the direct and indirect costs of injury creates opportunities to conduct studies in cost-effectiveness, a compelling tool when advocating for prevention measures in an environment of limited resources.

The importance of injury prevention efforts is pointed out by trauma mortality patterns. One-third to one-half of trauma deaths still occur in the field before any possibility of treatment even by the most advanced trauma treatment system.^9,10 Such deaths can only be decreased by prevention efforts. In terms of severely injured persons who survive long enough to be treated by prehospital personnel, very few “preventable deaths” occur in a modern trauma system with a well-run emergency medical system and designated trauma centers. Even among those who survive to reach the hospital, a significant portion of in-hospital deaths are directly related to injuries to the brain and occur despite optimal use of currently available therapy. In one study, out of 753 consecutive deaths, over 50% were deemed possibly preventable only by prevention efforts, with only 13% due to pulmonary embolus, multiorgan failure, and sepsis.¹¹ Hence, injury prevention is critical to further significantly reduce the toll of death caused by trauma. Moreover, prevention efforts can also decrease the severity of injuries and thus the likelihood of disability that arises after trauma.

This chapter provides the historic and scientific framework by which prevention efforts are implemented today. Although the list is not comprehensive, topics that cover both unintentional and intentional injury and site strategies that represent best practices and some newer promising practices in the United States are discussed. Many of these practices have evaluation and cost-effectiveness built in from program inception and stand as examples of the scientific principles presented in the chapter. Finally, the global implications of injury are reviewed. This includes injury as it affects low and middle-income countries and developing strategies in surveillance, prevention and injury control necessary to make a difference amongst populations at greatest risk.

History of Injury Prevention

Historically, injuries were seen as “accidents” that could not be predicted, and, therefore, could not be prevented. This limited perspective resulted in an unaggressive approach to injury prevention of restricted scope that had little effect.^12,13 Over the last 100 years, several visionary individuals had successive insights that established the public health basis for injury prevention. These frameworks resulted in a rational approach that now guides effective injury prevention.

In 1916, a volunteer pilot in the Canadian Royal Flying Corps named Hugh DeHaven was on his final training flight when his plane collided with another and fell 500 ft to the ground.¹⁴ The gunner of the plane died, but DeHaven survived with significant injuries, spending the rest of his military service as a clerk who was involved in the collection of bodies during World War I.¹⁴ He began to notice different injury patterns and began to theorize that the design of the plane’s interior may affect or even prevent the injuries sustained by its passenger. These observations led to the earliest developments of modern injury prevention. By applying engineering principles to injury events, DeHaven created the biomechanical foundation for injury that ultimately led to the development of automotive safety belts.^15,16

The epidemiologist John E. Gordon built on DeHaven’s foundation with another novel perspective by pointing out that injuries can be evaluated using the standard epidemiologic framework of host, agent, and environment (Table 3-2). Just like any other condition affecting human health, Gordon explained that injuries were not random, but occurred with recognizable patterns across time and populations.¹⁷ This conceptual evolution was a paradigm shift—from single-cause explanations of injury that inadequately described the injury event and, therefore, limited prevention opportunities to a multifactorial understanding of the components of injury. This would allow injuries to be studied from several perspectives and opportunities for prevention identified.¹⁸

The fundamental work done by DeHaven and Gordon applying public health principles to injury set the stage for the most notable of the early pioneers of injury prevention, William Haddon, the first director of the National Highway Traffic Safety Administration (NHTSA). Haddon is most well known for his expansion of Gordon’s epidemiologic framework for injury prevention, by incorporating a temporal element to the host-agent-environment schema, which ultimately became known as Haddon’s Matrix (Table 3-3).¹⁹ The pre-event phase allows us to examine the factors surrounding host, agent, and environment that influence the likelihood that an event capable of producing an injury will occur (such as a car crash). An example of a host factor in the pre-injury phase would be alcohol impairment, agent factors could include brakes or maintenance, while an environmental factor could be road condition. During the event phase, there are factors influencing the probability that the event (ie, car crash) will result in an injury, and if so, to what extent. A host factor during the event could be seatbelt use, an agent factor might be crush resistance of the car, and an environmental factor could be the presence or absence of dividers that would keep the car from ricocheting into ongoing traffic. In the post-event phase, these three components (host, agent, and environment) can be evaluated for factors that influence the ultimate consequences of injury.

This conceptual framework was further leveraged by Haddon to develop 10 strategies that formed the foundation of most current injury prevention and control efforts (Table 3-4).¹⁹ The underlying concept to most of these strategies is based on the work pioneered by DeHaven; that is, separating the injury-producing “energy” from the host.^18,19 Haddon’s work marks the most pronounced shift in the transition from a simplistic, single-cause, individual-level perspective of injury events to complex, multifactorial, societal-level causation. Haddon’s approach also integrated multidisciplinary involvement into injury prevention, including clinicians, epidemiologists, engineers, law enforcement agencies, policy experts, educators, and mental health experts.

Principles of Injury Prevention

Most interventions can be thought of as either being active or passive on the part of the person being protected. Active interventions involve a behavior change and require people to perform an act such as putting on a helmet, fastening a seatbelt, or using a trigger lock for a handgun. Passive interventions require no action on the part of those being protected and are built into the design of the agent or the environment, such as airbags or separation of vehicle routes and pedestrian walkways. Passive interventions are generally considered more reliable than active ones^19,20; however, many interventions that are considered passive still inherently carry an active component, even if it is at the societal or political level, such as passing legislation to require certain safety features in automobiles. The number of times an active intervention needs to be performed to be effective is also a consideration in terms of efficacy. For example, a seatbelt must be used each time to be effective, while a vaccine usually only requires active participation for a limited time interval for it to have long-term effectiveness.

Another framework often applied to injury prevention strategies is that of the following “three E’s”: (1) enforcement and legislation, (2) education and behavior change, and (3) engineering and environmental modifications. Initially, education was the main area of focus for injury prevention. If applied uncritically without a strong framework and thorough evaluation, behavior change through educational interventions in isolation can be difficult to achieve. A comprehensive report has suggested that the most effective interventions are engineering/environment, followed by enforcement, and lastly by education.²¹ Educational interventions are usually most effective when complemented with modalities from the other “E’s”; that is, the most effective injury strategies typically have components of all three. An example is the child safety seat, an engineering solution for injury prevention, which was only successfully implemented through successful education campaigns and careful law enforcement.²¹

Other factors that must be considered when choosing and implementing injury control strategies are fidelity versus adaptability. Fidelity refers to the measure to which a program is implemented as intended. Fidelity has been found to influence the measured effectiveness of an outcome.²² While fidelity to the program’s intended implementation is critical to achieving desirable outcomes, contexts may differ widely in a number of ways, ranging from socioeconomic characteristics of the population served to cultural nuances that may influence implementation of the program. Adaptability is the ability of a program to be modified so that it is applicable in a specific context. An effective injury control program needs to strike an appropriate balance between fidelity to established, evidence-based methodology, while being adaptable enough to maintain relevance to the specific population being served. Often, the fidelity and adaptability of a specific program will influence its prioritization among potential injury control interventions.

Prioritization of targets in injury control for intervention depends on multiple factors.¹⁸ The frequency and severity of a type of injury are fundamental to whether investments should be made to prevent or improve treatments for that injury; that is, having a solid base of evidence for the epidemiology of injury is key to prioritization. Certain injuries may occur frequently, but if the consequences of that injury in terms of severity are minimal, there may be a more important target for injury prevention or control. The cost of injuries in terms of direct health care costs and indirect societal and economic effects must also be considered. Effective arguments for implementing an injury control program can be made if savings in terms of averted injury-associated costs are demonstrated. Awareness of the importance of cost-effectiveness analyses and their potential as a tool for advocacy is steadily increasing.^23,24,25 Understanding of the resources available to fund and sustain the intervention is of primary consideration, as well, and will clearly influence the intervention chosen. Finally, less easily quantifiable but equally important are the acceptability and feasibility (including political) of a program in the community.¹⁸ When several strategies for injury control are available and found to be acceptable as potential interventions, prioritizing them may be difficult. Obviously, the most effective strategy proposed should be prioritized; however, often, a mixed strategy is most effective and should be used, if resources allow.²⁶ When choosing between primarily active versus primarily passive interventions, the passive intervention is usually favored as the more reliable approach.^19,20 Finally, sustainability of a potential program is essential if it is to provide long-term effect, so assessing the ability of a program to become ultimately accepted and sustained may play into the decision as to whether or not to adopt it. An “institutionalized” program is one that achieves ongoing support and commitment from the agency, organization, or community in which it is based.¹²

Certain common characteristics run through many successful injury prevention programs. These include a multidisciplinary approach and community involvement and should involve ongoing evaluation of both the process and outcome of the program. Depending on the targeted injury type, a program might involve contributions from the following: health care professionals, public health practitioners, epidemiologists, psychologists, manufacturers, traffic safety and law enforcement officials, experts in biomechanics, educators, and individuals associated with the media, advertising, and public relations as previously noted. Health care professionals might include those in primary care, such as pediatricians, and those involved in acute trauma care. Finally, individual members of the public might be involved.^20,27

Injury Control: From Surveillance to Dissemination

The public health approach can be applied to injury prevention and control as it is applied to any problem at the population level. This approach is comprised of the components described below¹⁸:

1. Surveillance

2. Risk factor identification

3. Ascertaining natural history

4. Intervention

5. Evaluation

6. Dissemination

The components of a comprehensive injury prevention program are demonstrated in Box 3-1.

Program Evaluation

Evaluation of an injury prevention program is an essential component of any program, allowing implementers to assess program effectiveness and make appropriate improvements. It also provides quantitative information for funders, increasing the program’s accountability and support, and ensures that resources are being used in a beneficial and cost-effective way.^28,29 While the science of program evaluation is extensive, a comprehensive review is beyond the scope of this discussion. Therefore, a brief overview of the necessary components and underlying standards is provided.

Program evaluation should be built into the program from inception, including during the development of theoretical frameworks supporting the program’s premise. For example, a logic model developed in anticipation of forming a program should be assessed for the validity of underlying assumptions before implementation of the program.²⁹ Early stakeholder engagement is key to this process, as stakeholders can often identify gaps in the theoretical basis of a proposed program and help supply alternatives or solutions. As a program is developed, it is important to have discrete, agreed-upon metrics by which to assess the program, so that progress can be measured and seen by all those involved. One helpful approach is to achieve consensus responses to the series of essential questions outlined in Box 3-2. Included are examples of responses based on a violence intervention program.

Program evaluation can focus on two broad areas, including formative evaluation and summative evaluation (including results, impact, and outcome evaluation).²⁹ In order to address these two areas, a combination of qualitative and quantitative evaluation metrics is often needed. Formative measures may include measurable goals inherent to the program’s development, such as acquisition of human and capital resources or construction of program components. Summative evaluation measures are specific to the delivery of the program, outcomes of interest that the program is intended to influence, and the impact that the program is having on the community.²⁹ These measures can be a combination of process measures, impact measures, and outcome measures.³⁰ Process measures include measuring the success of delivering the program’s services to the intended community. An example using a falls prevention program would be the number of people educated or number of handrails installed in response to program initiatives. Measuring impact means evaluating the immediate, short-term effects of the program. For a falls prevention program, this could be noting an increase in knowledge about falls prevention among program participants. Outcome measures for this same program would include the number of fall events or fall-related injuries seen before and after implementation of the program. Selection of these measures should be done early in program development, so that evaluation is built into the infrastructure of the program. For injuries, data sources used to evaluate outcome measures vary in terms of capture and resource expenditure (Fig. 3-1). Well-designed community-based surveys with sophisticated sampling strategies are costly and not sustainable on a longitudinal basis, but they provide a good estimate of injury incidence per population. Trauma registries are extremely useful tools for injury surveillance and are present in all level-I trauma centers; however, the population captured is subject to selection biases based on severity and geography. Understanding the nature of the data and its inherent selection biases are critical to building and interpreting an injury surveillance system.

The steps in program evaluation have been well-defined by the United States Centers for Disease Control and Prevention, among others (Fig. 3-2).^31,32,33 The six steps are as follows:

1. Engage stakeholders (people involved in program operations, the population served, funders, and others affected).

2. Describe the program (needs assessed, expected effects, context, logic model/theoretical framework, activities).

3. Focus the evaluation (identify the measurable effects that are most important to stakeholders).

4. Gather the evidence (indicators, data sources, quality and quantity of data available).

5. Justify conclusions (correlate conclusions using evidence gathered and assess this conclusion against predetermined standards set by the stakeholders).

6. Share lessons (dissemination of results and lessons learned improves the likelihood that the program will be used).

The standards underlying these six steps strive to ensure that the program evaluation will be useful to users and stakeholders, ethically conducted, as well as accurate and feasible.^31,32 Ultimately, program evaluation should result in improvement of the program, identification of successful and unsuccessful components, and ensure that we invest in strategies that work while discontinuing those that do not.

For those interested in a more comprehensive review of program evaluation or further in-depth reading on the techniques and tools of program evaluation, references are provided.^{29,31,32,33,34}

Motor Vehicle Safety—Occupants

Motor vehicle safety and injury prevention measures provide a comprehensive example of proven active interventions, passive engineering, legislation, and enforcement strategies that have been modified over decades. In addition, due to detailed surveillance over time, some newer strategies have recently been implemented to address current risk factors such as use of cell phones and targeted strategies for teenage drivers, the highest risk group.

Much has been accomplished to make motor vehicles safer. Engineering features make it less likely for a vehicle to crash, referred to as crash avoidance, which takes into account such features as brakes, headlights, triple brake lights, and signals. Automotive safety also includes engineering features that make occupant injury less likely in the event of a crash. This is referred to as crashworthiness and takes into account such features as collapsible steering columns, shatter-proof glass, and improved side impact protection. These improvements have resulted from both improved car design on the part of the automobile manufacturers and regulations from NHTSA, in the form of Federal Motor Vehicle Safety Standards (FMVSS).

One of the greatest advances in automotive safety was the realization that a significant component of the injuries sustained in crashes were due to ejections and to secondary collision of the occupant with the vehicle interior after the vehicle had collided with another object. This understanding led to the development of seatbelts to allow occupants to “ride down” the crash, dissipating their kinetic energy more slowly and in a controlled fashion. It is estimated that seat belt use reduces serious crash-related injury and death by about half. Adding (not substituting) airbags provides even greater protection for adults.^35,36

Despite the major progress overall as a result of engineering and enforcement regarding seatbelts, there remains a population of people least likely to wear seatbelts—teenagers. Of the teenagers who died in motor vehicle crashes in 2012, 55% were not wearing seatbelts.³⁷ Seatbelt use is an active prevention measure. Primary enforcement and education by parents and health care providers are strategies that can work, even when facing the challenge of the teen still in a steep behavioral development phase in cognitive growth.

Graduated Licensing

Teen drivers have the highest crash risk per miles traveled of any group; however, newer prevention strategies, most notably graduated licensing, are having positive results on rates of serious motor vehicle crashes. Graduated licensing laws are now present in all 50 states and the District of Columbia and allow for teens to mature and develop skills during an intermediate step. The initial license, for example, may restrict night driving or having young passengers except family members in the car with the new driver. Along with enforcement of drinking and driving laws and properly fitted child car seats, graduated licensing has significantly improved the rate of serious motor vehicle crashes in the United States.³⁸

Strategies Regarding Distracted Driving

Along with the convenience of cellular phones for conversations and texting comes the risk of distracted driving. Distracted driving is thought to be responsible for more than 9 deaths and 1100 motor vehicle injuries daily in the United States, an issue that appears to be much worse than in other places with as much cellular access such as Europe.^37,39 With the raised awareness of the dangers of distracted driving, many states have enacted strict laws regarding texting and driving and have legislated for “hands-free” cellular phone use while driving. A number of laws limiting cellular phone use amongst federal employees and train operators have also been enacted.

Motor Vehicle Safety-Pedestrians

Injury prevention for pedestrians exemplifies the importance of comprehensive strategic planning amongst the community, government, and health care agencies. In 2012, over 4700 pedestrians were killed and another 76,000 were injured in the United States. Vulnerable populations include the elderly, children, and the mentally ill.⁴⁰ As low and middle-income countries industrialize at a rapid rate, improvements in road traffic engineering have lagged behind, causing a growing threat to pedestrians in many countries. Passive strategies such as complete separation of pedestrians from motor vehicles have had proven success at reducing risk, but may not be feasible. Other engineering strategies to create a safer environment such as countdown signals (particularly around senior facilities), flashing crosswalks, pedestrian lead time signals, and “bulb outs” have had varying rates of success.

Strategic Planning

Prevention of pedestrian injuries often requires a multidisciplinary approach involving community activists, engineering experts, public health departments, police and fire departments, legislators, and public health researchers. An example of a promising practice is the strategic plan “Vision Zero Initiative.” The initiative was created in Sweden and based on the public health principle “we are human and we make mistakes,” but the environmental design should keep us safe, and no loss of life is acceptable. As such, the initiative places the main burden for safety on comprehensive system design. Plans first enacted in Sweden in 1994 have led to clear reduction in pedestrian deaths and injuries, despite growing amounts of traffic. The initiative has now been adopted in several cities worldwide, including New York City, Chicago, and San Francisco. Central to strategic planning for Vision Zero is surveillance.⁴¹ Trauma centers can play a major role in this component given that there is evidence that, in the United States, police data only capture a segment of pedestrian and bicycle injuries.^42,43 Trauma center data can serve to fills the gaps and partner with local initiatives to collaborate and directly inform for strategic planning and policy advocacy. Along with comprehensive plans for road traffic safety, analysis of cost-effectiveness should be rolled into the long-term planning. Strategies that are cost-effective will require maintenance for sustainability. Modeling that with the direct and indirect cost of pedestrian injury is essential.

Prevention of Falls

More than one-third of adults over 65 years fall each year in the United States, and, for over half of those individuals, it is not the first fall. One in ten falls are deemed serious, and over 10% of emergency department visits are due to falls. Individuals who are mentally ill are also at higher risk for falls, but this section will focus on the elderly patient. Risk factors are well known and include visual impairments, polypharmacy leading to disequilibrium and gait disturbances, home hazards such as loose rugs and steps, and lack of grab bars. The costs of falls in the elderly, both personally and financially, are very significant. Severe traumatic brain injury, particularly with increases in usage of antiplatelet therapies and warfarin, poses great threats to life and independence.^44,45 The direct medical cost of elderly falls exceeds $20 billion for those that are nonfatal.⁴⁶

These risk factors above, however, are preventable. A number of programs in fall prevention targeting the risk factors and thereby demonstrating reduction of falls and fall recidivism has been implemented over the past decade. Many of these programs focus on home assessments and implementation of safety measures such as securing rugs, creating ramps, and installing grab bars. In addition, physical therapy programs working specifically on gait and balance, reviews of medications and potential medication interactions, and vision screening have all played a successful role in risk reduction strategies. Hospital-implemented efforts in fall prevention including screening and implementation have been led in part by the Veteran’s Administration. These have proven to be promising and have been a way that trauma centers with a high burden of elderly falls can fulfill their injury prevention mandate and provide an active prevention strategy. These are developed in conjunction with senior community resource centers and other groups focused on risk reduction.^47,48,49

Prevention of Suicide

In 2013, suicide was the tenth highest cause of death for all ages in the United States. It is estimated that 800,000 people die worldwide from suicide annually. Globally, risk factors are present in marginalized and discriminated groups. In many countries, including the United States, risk factors also include mental illness, prior suicide attempts, personal loss, financial loss, chronic pain, substance abuse, and trauma. Protective factors and resiliency often require long-term care and counseling and are dependent upon access to that care.⁵⁰ A comprehensive strategy for suicide prevention is well-outlined by the CDC in the guide Promoting Individual, Family and Community Connectedness along with focused treatment of mental illness and substance abuse.⁵¹ The trauma center can serve as a portal by which individuals who have attempted suicide can be provided with resources and the means to reduce harm.

Prevention of Youth Violence

It has been nearly two decades since the Surgeon General at the time, C. Everett Koop, recognized interpersonal or youth violence as a public health issue. Since that time, health providers from primary care physicians to trauma surgeons have adopted a public health model. This has included assessment of individual risk and protective factors, developing strategies for reduction in harm by implementing programs, evaluating programs, and exporting programs that are promising. In the United States, there are over 25 hospital-based violence intervention programs that target youth and young adults who have been violently injured. The public health approach follows the principles of Trauma Informed Care as follows: (1) realizes the widespread impact of trauma and understands potential paths to recovery; (2) recognizes the signs and symptoms of all trauma in clients and families; (3) responds by fully integrating knowledge about trauma into policies, procedures and practices; and (4) seeks to actively resist trauma recidivism.⁵² Conversely, programs based on “scared straight” approaches have not been successful.⁵³ Three specific guiding components for implementation in many hospital based programs are as follows: (1) recognition that when an individual is injured, there is a “teachable moment” during which time that individual is most open to risk reduction strategies; (2) culturally aware and competent case managers/intervention specialists approach the individual at the bedside and provide long-term follow-up care; (3) case managers assess needs and assist individuals over time to find resources for risk reduction available in the community. Evaluation including feasibility, utility, intermediate and long-term results, and cost-effectiveness studies have been conducted. Results are promising with demonstration of successful enrollment and retention (feasibility), risk reduction when looking at intermediate outcomes, reduction in the injury recidivism rate when looking at long-term outcomes, and demonstration of cost-effectiveness.^23,54,55 Some programs have been successful at reducing injury in the most vulnerable populations by securing funding within the city budget through working with legislators and departments of public health. Technical support and advocacy is available for trauma centers interested in implementing a violence intervention program through the National Network of Hospital Based Violence Intervention Programs (NNHVIP.org).

Global Burden of Injury: Mortality and Non-Fatal Consequences

Growing attention has been placed on the burden of injury worldwide and highlighting trauma as a global public health issue. As countries industrialize, road traffic increases along with the risk of injury, especially in contexts where commensurate improvements in road safety have not been achieved.² As mentioned at the outset of this chapter, over 90% of the 5.8 million deaths each year due to injury occur in low and middle income countries, where trauma systems are least developed.

As injury rates and fatalities exhibit an overall decline in high income countries, the burden of injury in low and middle income countries continues to rise.^56,57 The etiology of this is likely multifactorial. First, most people in the world live in low and middle income countries.⁵⁸ Also, industrialization is associated with an increase in vehicle ownership, traffic density, and traffic mix, all of which contribute to an increased incidence of injury.⁵⁹ Additionally, the injury case fatality rate in low and middle income countries is higher than in high income countries, likely due to weaker implementation of prevention efforts and less well-developed prehospital and hospital care. A person injured in a low or middle income country has twice the likelihood of dying from his or her injuries than a similarly-injured person in a high income country.⁹ As surgery is an integral component of trauma care, it is informative to discuss the distribution of surgical services across countries of different economic strata. While only 15% of the world’s population lives in wealthy countries, 60% of the operations done each year are in these countries. Only 3.5% of the operations performed globally each year are in poor countries, which includes 35% of the global population.⁶⁰

Decreasing the Global Burden of Injury: Opportunities and Challenges

The magnitude of the global burden of injury is clearly great, yet trauma is often not discussed among the world’s Global Health priorities. Of the US $4 billion budgeted by the World Health Organization (WHO) each year, less than 1% is spent on injury. This amount is grossly disproportionate to the 12% of the world’s disease burden attributable to injury.⁶¹

Recent attention on the importance of trauma as a public health priority has led to several encouraging initiatives. The WHO has published several guidelines geared toward low and middle income countries that establish the essential components of trauma care and offer guidance toward implementing cost-effective programs in trauma quality improvement.⁶² These were largely in response to a landmark World Health Assembly (WHA) resolution on trauma care (60.22) calling for improved technical support from WHO for stakeholder countries to address the growing burden of trauma.⁶³

In 2015, the growing appreciation of the burden of surgically treated diseases in low- and middle-income countries sparked several landmark developments. The Lancet Journal created a Commission on Global Surgery, representing contributions from 110 countries. This resulted in a series of reports, publications and recommendations to guide improvements toward equitable access to affordable surgical care globally.¹ In March, 2015, the 3rd edition of the Disease Control Priorities was released, which featured a renewed focus on surgical issues. Additionally, the WHO and the United Nations launched a Decade of Action for Road Safety in 2011 in over 100 countries, demonstrating the importance of prevention of injuries related to road traffic and treatment of associated trauma.⁶⁴

Injury Control in Low and Middle Income Countries

The basic principles of injury prevention previously outlined in this chapter are universal; however, the application of these principles may vary by context. For example, the distribution of injuries related to road traffic has been shown to vary by country, with pedestrians and drivers of two-wheel vehicles found to be particularly vulnerable in certain low and middle income countries.^65,66,67,68 Some reports estimate that nearly 55% of road traffic deaths in Africa are due to pedestrian injury, compared to 15% or less in the United States or Europe.^69,70 Similarly, scald burns appear to be more frequent in high-income countries than in low and middle income countries, while flame burns are more frequent in low and middle income countries.^{69,71,72,73,74} These differences in the patterns of injury underscore the importance of comprehensive and robust injury surveillance systems to inform evidence-based interventions. In high income countries, a cornerstone of these systems has been hospital-based trauma registries, a surveillance tool which is increasingly used in low and middle income countries.^{75,76,77,78,79} In addition to regionally accurate injury surveillance data, effective injury prevention efforts can only be successful with early engagement of stakeholders and careful assessments of feasibility to tailor interventions to local contexts.

Speed Bumps

An example of a cost-effective method of reducing highway speeds is the strategic placement of speed bumps. One speed bump is estimated to cost about US $1000 to build and is expected to last 10 years. When modeled for the world’s most dangerous intersections where 10% of deaths occur, speed bumps are among the most effective and cost-effective public health interventions available, costing approximately US $100 for life saved and only US $3.26 per DALY achieved.⁸⁰

Helmet Use

Helmet laws are another injury prevention intervention that has been studied in low and middle income countries. In Thailand, enactment of a helmet law was associated with a fivefold increase in helmet use among motorcyclists and a concomitant reduction in head injuries by 41% and deaths by 21%.⁸¹ The cost-effectiveness of this intervention was estimated to be US $467 per DALY averted.⁸⁰ In Vietnam, a helmet law was adopted more recently after it was found that 60% of the over 11,000 annual road traffic fatalities in that country occurred in motorcycle users. This public health problem was addressed through a combination of legislation, social marketing, and enforcement, and was ultimately associated with significant decreases in injury events, serious injuries, and deaths captured through hospital and police data sources.⁸²

Seat Belts

Improving the use of seat belts through policy and legislation is another injury prevention strategy recommended by the WHO to improve traffic safety.² While seat belt use has become widespread in high income countries like the United States, the practice and enforcement in low and middle income countries is less prevalent. As part of the Road Safety in 10 Years project, enforcement campaigns advocating for seat belt use and speed control in several low and middle income countries have shown promise both in increased utilization and decreased injuries.^83,84

One important concept when considering interventions in road traffic safety is that implementing a multifaceted intervention tends to be both more effective and cost-effective than implementing a single intervention. For example, implementing a helmet law in combination with a seatbelt law in the same region would not only result in a greater reduction in injuries and deaths, but be more cost-effective than only one of these interventions. This is because the infrastructure for enforcing one intervention is shared by the other, mitigating the cost.⁸⁵

Prevention of Drowning

Drowning is the third leading cause of death due to unintentional injury, with more than 70% of these deaths occurring in low and middle income countries.⁸⁶ Africa has the highest rate of DALYs due to drowning globally, at 247 per 100,000 population. This is approximately 3.5 times the number of DALYs due to drowning in the Americas.⁶⁹ Given the disparity in drowning deaths disproportionately affecting the world’s poor and the documented success of drowning prevention efforts in high income countries, there have been some recent initiatives in low and middle income countries. A community-based intervention in Bangladesh that involved both education and integration of playpens and door barriers for infants found that families who were provided the intervention improved their child supervision practices.⁸⁷ Another program in Bangladesh, Prevention of Child Injuries through Social-Intervention and Education (“PRECISE”), employed both an educational component that focused on teaching children to swim (SwimSafe) and a childcare component. This targeted children aged 1–5 years, who are at the highest risk of drowning, by enrolling them in village-based crèches (Anchal program). Not only were both programs associated with a decreased risk of drowning among enrolled children, but the programs were found to be cost-effective both individually and as a combined intervention.⁸⁸

Tertiary Prevention

With the increased focus on injuries as a global public health problem has come an evolving awareness of the importance of strengthening trauma care in resource-constrained settings. The WHO has published several resources aimed at providing technical support to health care providers, policy makers, and hospital administrators to improve trauma care in their context, regardless of resources.^57,62,89 Several programs in low and middle income have demonstrated improvements in the prehospital care of trauma patients using context-appropriate innovations.^{90,91,92,93,94} In the hospital setting, quality improvement (QI) programs have been used as cost-effective means to improve trauma care in all countries.⁶² Specific applications of QI techniques, including creation of a trauma registry, the definition of key performance indicators, application of audit filters, and root cause analysis have been associated with a reduction in both preventable deaths and overall mortality in trauma patients in Thailand.^95,96,97 Similarly, in Pakistan, the utilization of QI principles led to the creation of trauma services. This intervention was associated with significantly decreased odds of both death and complications after implementation.⁹⁸

The field of injury prevention and control has made dramatic inroads into reducing the toll of death and disability. Particularly in high income countries, prevention measures against active and passive injury have been successful in increasing the safety of road users, populations at risk for falls or burns, and potential victims of violent injury. Through comprehensive evaluations and the right mix of fidelity and adaptability, efforts in decreasing both intentional and unintentional injury are demonstrating intermediate and long-term successes. With over 90% of injury deaths occurring in low and middle income countries, appropriate attention is now shifting to worldwide surveillance and strategic planning for injury prevention. It is only through this work that the burden of global injury can be improved.

Surgeons have a unique opportunity to participate in all components of prevention from surveillance to programming to evaluation and advocacy. Surgeons see patients during that unique “window of opportunity” after injury, making them powerful advocates not only to individuals and community organizations, but to legislators, as well. The injury event, and similarly the hospital itself, is a promising portal of entry into prevention programs. Surgeons have spearheaded projects that have clarified the mechanisms of particular injuries and have implemented and studied programs that can have impact. Surgeons are a vital partner in the multidisciplinary approach necessary to make an appreciable difference in injury-related death and disability globally.