A Comprehensive Guide to Preventing Motor Vehicle Crashes and Saving Lives

Table of Contents

• Introduction: The Scale of the Problem
• The Safe System Approach: A New Way to Think About Road Safety
• Safer People: Addressing Driver Behavior and Vulnerable Groups
• Safer Roads: Designing Forgiving Infrastructure
• Safer Vehicles: Technology That Protects You
• Safer Speeds: Why Speed Management Matters
• Postcrash Care: Improving Emergency Response
• Comprehensive Prevention Framework
• Conclusion: Our Shared Responsibility
• Source Information

Introduction: The Scale of the Problem

The human cost of motor vehicle crashes in the United States is staggering and unacceptable. In 2021 alone, 42,939 people lost their lives on American roadways, making traffic incidents the leading cause of death for people aged 5 to 29 years. Despite ongoing safety efforts, the United States has much higher fatality rates—both per person and per mile traveled—compared to other high-income countries.

This crisis is not inevitable. Research using naturalistic driving data (real-world driving behavior collected through advanced instrumentation) provides unprecedented insight into the behaviors and circumstances that lead to crashes. Combined with technological advances, we now have the tools to reverse this preventable trend and make meaningful progress toward universally safe mobility for all road users.

The Safe System Approach: A New Way to Think About Road Safety

In 2021, the U.S. Department of Transportation adopted the evidence-based Safe System Approach, which encompasses six fundamental principles that change how we think about road safety:

• Death and serious injuries are unacceptable - We must aim for zero preventable deaths
• Humans make mistakes - Our systems should accommodate human error
• Humans are vulnerable - Our bodies have limited physical tolerance to crash forces
• Responsibility for safety is shared - Everyone has a role in safety, not just individual drivers
• Safety is proactive - We should prevent crashes rather than just respond to them
• Redundancy is crucial - Multiple layers of protection ensure safety if one fails

This approach has successfully reduced traffic fatalities in other countries, particularly in Europe. The responsibility for roadway safety is shared equally among all stakeholders—road users, transportation designers, vehicle manufacturers, policymakers, administrators, and healthcare professionals are all active participants in eliminating roadway fatalities.

Safer People: Addressing Driver Behavior and Vulnerable Groups

The Safer People component addresses all road users—drivers, passengers, pedestrians, and cyclists. Crash risk isn't evenly distributed across all drivers. Young drivers (16-20 years old) have substantially higher fatality rates—60.3 male drivers and 25.5 female drivers per 100,000—compared to 18.5 drivers per 100,000 for all age groups combined.

Graduated driver's licensing policies, now used in all 50 states, restrict teenagers from high-risk situations like late-night driving and driving with teenage passengers. These policies have had varying success in reducing teenage crash risk. Technological solutions that monitor driver performance and provide feedback during the learning period show promise in improving safety for young drivers.

Significant racial and ethnic disparities exist in crash rates. When accounting for miles traveled and mode of transportation:

• American Indian and Alaskan Native persons are more likely to be in fatal crashes than non-Hispanic White persons
• Black or African American persons are more likely to be in fatal crashes than non-Hispanic White persons
• Asian persons are half as likely to die in roadway incidents as non-Hispanic White persons

Pedestrian safety shows particularly concerning disparities. Per mile walked:

• American Indian and Alaskan Native pedestrians are 5.1 times more likely to die than White pedestrians
• Non-Hispanic Black or African American pedestrians are 2.1 times more likely to die than non-Hispanic White pedestrians

These disparities are especially troubling because pedestrian fatalities are increasing in the United States, and the connection between race, ethnicity, and socioeconomic status means society's most vulnerable members are disproportionately affected by traffic crashes.

High-Risk Behaviors That Endanger Everyone

Several dangerous behaviors significantly increase crash risk:

• Alcohol and drug-impaired driving: Despite decreases since the 1980s, 31% of all fatal crashes in 2021 involved intoxicated drivers. Over 50% of fatally injured road users test positive for one or more drugs, most commonly alcohol, followed by cannabinoids, stimulants, and opioids
• Lack of seat belt use: While seat belt use has increased from 75% in 2002 to nearly 92% twenty years later, not using seat belts still contributes to 50% of fatalities involving vehicle occupants
• Distracted driving: Driver distraction contributes to 29% of all motor vehicle crashes, especially among young drivers. Observational studies show that 4-5% of drivers aged 16-24 are physically interacting with a cell phone at any given moment

Laws incorporating severe penalties with high-visibility enforcement (like sobriety checkpoints) effectively discourage drunk driving and encourage seat belt use. Emerging technologies that passively detect driver intoxication show promise, including ignition interlocks mandated by the 2021 Infrastructure and Jobs Act.

Safer Roads: Designing Forgiving Infrastructure

The roadway-design component of the Safe System Approach emphasizes accommodating inevitable human mistakes to eliminate fatalities and serious injuries. Roadways must be designed so that impact forces in any crash remain below the threshold that causes fatal injuries to occupants.

For example, reducing speed limits and improving traffic circle (roundabout) design can reduce fatalities and serious injuries at intersections—which account for over 25% of all traffic fatalities—by 70-80%.

Pedestrian fatalities have been rising since 2011, with most occurring:

• In urban locations (82%)
• At midblock or non-intersection locations (75%)
• In darkness (77%)

Effective countermeasures include barriers between sidewalks and roadways to separate user types and discourage dangerous midblock crossings. Cyclist deaths have also increased over the past decade, and infrastructure that separates cyclists from motor vehicles or lowers vehicle speeds significantly improves cyclist safety.

When separation isn't feasible, roads should be redesigned to decrease collision likelihood (through better visibility, lighting, and enhancements) or reduce crash energy (by narrowing lanes to lower speeds).

Safer Vehicles: Technology That Protects You

Modern vehicles incorporate extensive safety features designed to enhance survivability in crashes:

Passive safety systems protect occupants during a crash and include:

• Energy-absorbing vehicle structures
• Advanced airbag systems
• Seat belts with pretensioners (devices that tighten seat belts during a crash)

These systems reduce energy transferred to vehicle occupants during crashes, decreasing injury severity. Independent crash testing and public rating systems encourage continuous improvement of these safety features.

Active safety systems help prevent collisions before they happen and include:

• Forward-collision warnings
• Lane-departure warnings
• Traction control
• Electronic stability control

Recent regulatory action will make automated emergency braking—which automatically applies brakes when detecting imminent collisions with vehicles or pedestrians—standard in new vehicles by 2029. Emerging steering systems that actively assist with evasive maneuvers may further reduce crash severity.

Driver-monitoring systems that detect distraction and drowsiness based on head position and eye gaze are being introduced in vehicles and show promise for enhancing safety when combined with partially automated driving systems.

Safer Speeds: Why Speed Management Matters

Speeding was cited as a factor in 28% of all fatal crashes in 2021, with younger and male drivers disproportionately likely to speed. During the COVID-19 pandemic, while overall traffic decreased, the risk of vehicles traveling 10-15 miles per hour above speed limits increased by 30-40%.

High-visibility enforcement has proven effective at reducing dangerous speeds, indicating that enforcement plays a crucial role in saving lives. Automated enforcement using cameras and sensors that detect vehicle speed and collect images of license plates and drivers reduces injury crashes by 20-25% according to international data.

Despite its effectiveness, automated enforcement isn't widely used in the United States due to public opposition and concerns about privacy and equity. Public policy administrators must address these concerns to enable wider adoption of this life-saving technology.

Postcrash Care: Improving Emergency Response

Prompt, effective medical care is essential for survival and recovery after traffic crashes. Longer emergency medical services (EMS) response times and greater distances to level I or level II trauma centers are associated with higher fatality rates.

These factors are particularly critical for crash victims in rural areas—39% wait 1-2 hours before hospital arrival compared to 10% of urban crash victims. Decisions about closing rural healthcare facilities and locating new ones must carefully consider impacts on motor vehicle crash fatalities.

Crash notification systems that detect collisions and automatically alert emergency services should be broadly integrated into vehicles and infrastructure. These systems can reduce response times and transmit crash details to help EMS prepare appropriate treatments and arrange the best available transport.

While many car companies offer these systems, most are subscription-based and may not be well-integrated into local EMS frameworks. Some smartphone developers are integrating crash-detection and EMS-notification systems into their software, and advances in cellular network coverage in rural areas may provide important improvements in crash outcomes.

Comprehensive Prevention Framework

The Haddon matrix provides a comprehensive framework for understanding motor vehicle crash prevention across different phases and factors:

Prevention Phase (before crash factors develop):

• Effective driver training and education
• Driver-assistance systems like adaptive cruise control
• Distraction-mitigating interfaces
• Driver-monitoring systems
• Road designs that provide clear, understandable information to drivers
• Road diets (reducing number and width of travel lanes)
• Marked pedestrian and bicycle lanes
• Enhanced graduated driver licensing
• Effective motor vehicle regulations
• High-visibility law enforcement presence
• Automated enforcement
• Meaningful penalties for violations

Precrash Phase (seconds before a crash occurs):

• Swift driver reaction to alerts and warnings
• Successful evasive maneuvering
• Active safety features (forward-collision warning, automatic emergency braking)
• Rumble strips
• High-friction surfaces
• Ample road shoulder space
• Alerts about nonmotorists

Crash Phase (during the collision):

• Proper body and seat position
• Vehicle crashworthiness and passive safety devices (seat belts, airbags)
• Roadside obstacles designed to break away safely
• Clear space adjacent to roadway
• Guardrails that redirect or absorb energy

Postcrash Phase (after the collision):

• Rapid emergency response and treatment
• Quality prehospital and emergency department care
• Crash notification systems that automatically alert emergency responders
• Vehicle designs that allow victim extraction and maintain battery/fuel system integrity
• Traffic management near crash sites
• Variable-message signage to redirect traffic
• Proximity and capacity of emergency services
• Protocols and policies enabling rapid response

Similar to preventive medicine, crash prevention and mitigation may contribute more to reducing fatalities than simply improving postcrash care, with the additional benefit of reducing all injuries and associated costs.

Conclusion: Our Shared Responsibility

The success of the Safe System Approach requires that we all become active partners in eliminating motor vehicle fatalities and serious injuries. This shared responsibility extends to road users, vehicle manufacturers, transportation designers, policymakers, administrators, and healthcare professionals.

The evidence-based strategies outlined in this review—addressing human behavior, vehicle technology, road design, speed management, and emergency response—provide a comprehensive roadmap toward a future with no preventable traffic deaths. By implementing these approaches with redundancy and proactive safety measures, we can dramatically reduce the devastating toll of motor vehicle crashes on American families and communities.

This isn't just about better laws or smarter technology—it's about fundamentally changing how we think about road safety and recognizing that every stakeholder has a vital role to play in protecting human lives on our roadways.

Source Information

Original Article: "Motor Vehicle Crash Prevention" by Sheila G. Klauer, Ph.D., and Zachary R. Doerzaph, Ph.D.

Publication: The New England Journal of Medicine, 2025;393:479-86

DOI: 10.1056/NEJMra2216360

This patient-friendly article is based on peer-reviewed research and aims to make complex medical information accessible to educated patients and their families while preserving all essential data and findings from the original research.