Demographic adjustments to driver death rates by vehicle type and size.

Objective: Driver death rates per million registered vehicles are often used to compare the real-world crash experiences of vehicles of different types and sizes. However, these rates are affected by the risky behavior of drivers (e.g.

Changes in Traffic Crash Rates After Legalization of Marijuana: Results by Crash Severity.

Objective: The objective of this study was to estimate the effects of marijuana legalization and the subsequent onset of retail sales on injury and fatal traffic crash rates in the United States during the period 2009-2019.

Method: State-by-state quarterly crash rates per mile of travel were modeled as a function of time, unemployment rate, maximum posted speed limit, seat belt use rate, alcohol use rate, percent of miles driven on rural roads, and indicators of legalized recreational marijuana use and sales.

Results: Legalization of the recreational use of marijuana was associated with a 6.

Potential lives saved by in-vehicle alcohol detection systems.

Objectives: The objective of this study was to estimate the number of crash deaths specifically attributable to alcohol-impaired driving, with a focus on various strategies for introducing vehicle-based solutions. If alcohol detection systems are standard in all new vehicles, how many lives could be saved in the near term, and how long will it take to essentially eliminate alcohol-impaired driving? Alternatively, if such systems are offered as an option, how many lives could be saved?

Methods: Fatal crashes in the United States during 2015-2018 were classified by the highest driver blood alcohol concentration (BAC) and the corresponding age category of that driver. Based on the estimates of relative risk (RR) for a given driver group, eliminating alcohol in the driver's blood should lower risk by the attributable proportion, 1 - 1/RR.

Effects of Washington State's alcohol ignition interlock laws on DUI recidivism: An update.

Objective: The objective of this study was to examine the effects of changes to Washington State's alcohol ignition interlock laws: moving issuance of interlock orders from the courts to the driver licensing department (July 2003); extending the interlock order requirement to all persons convicted of driving under the influence (DUI; June 2004); allowing an interlock in lieu of an administrative driver's license suspension (January 2009); and requiring proof of interlock installation to reinstate the driver's license (January 2011).

Method: Trends in conviction types, interlock installation rates, and 2-year cumulative recidivism rates were examined for first-time and repeat offenders with convictions stemming from DUI arrests during 1999-2012. Autoregressive integrated moving average (ARIMA) models examined the association between law changes and installation rates, law changes and recidivism rates, and installation rates and recidivism rates.

Effects of an integrated collision warning system on teenage driver behavior.

Introduction: Crash warning systems have been shown to provide safety benefits, but no studies have examined how teenagers respond. This study sought to find out whether young, inexperienced drivers change behavior in response to warnings.

Methods: Forty 16-17 year-olds drove an instrumented vehicle equipped with a system that warned for lane departures and potential rear-end and lane change/merge crashes.

Relationship of traffic fatality rates to maximum state speed limits.

Objectives: The objective of this study was to examine the safety effects of increases in U.S. state maximum speed limits during the period 1993-2013.

Relationship of Near-Crash/Crash Risk to Time Spent on a Cell Phone While Driving.

Objectives: The objective of this study was to examine in a naturalistic driving setting the dose-response relationship between cell phone usage while driving and risk of a crash or near crash. How is the increasing use of cell phones by drivers associated with overall near-crash/crash risk (i.e.

Secondary Behavior of Drivers on Cell Phones.

Objectives: The objective of this study was to determine whether cell phone use by drivers leads to changes in the frequency of other types of potentially distracting behavior. There were 2 main questions of interest: (1) As each driver changes cell phone use, does he or she change the amount of driving time spent on other distracting behavior? (2) As each driver changes cell phone use, does he or she change the amount of driving time spent looking away from the driving task?

Methods: Day-to-day driving behavior of 105 volunteer subjects was monitored over a period of 1 year. The amount of driving time during each trip spent on tasks secondary to driving (or looking away from the driving task) was correlated to the amount of time on a cell phone, taking into account the relationships among trips taken by the same driver.

The Effects of Vehicle Redesign on the Risk of Driver Death.

Objectives: This study updates a 2006 report that estimated the historical effects of vehicle design changes on driver fatality rates in the United States, separate from the effects of environmental and driver behavior changes during the same period. In addition to extending the period covered by 8 years, this study estimated the effect of design changes by model year and vehicle type.

Methods: Driver death rates for consecutive model years of vehicle models without design changes were used to estimate the vehicle aging effect and the death rates that would have been expected if the entire fleet had remained unchanged from the 1985 calendar year.

Real-world injury patterns associated with Hybrid III sternal deflections in frontal crash tests.

Objective: This study investigated the relationship between the peak sternal deflection measurements recorded by the Hybrid III 50th percentile male anthropometric test device (ATD) in frontal crash tests and injury and fatality outcomes for drivers in field crashes.

Methods: ATD sternal deflection data were obtained from the Insurance Institute for Highway Safety's 64 km/h, 40 percent overlap crashworthiness evaluation tests for vehicles with seat belt crash tensioners, load limiters, and good-rated structure. The National Automotive Sampling System Crashworthiness Data System (NASS-CDS) was queried for frontal crashes of these vehicles in which the driver was restrained by a seat belt and air bag.

Washington State's alcohol ignition interlock law: effects on recidivism among first-time DUI offenders.

Objective: To examine the effects of changes to Washington State's ignition interlock laws: moving issuance of interlock orders from courts to the driver licensing department in July 2003 and extending the interlock order requirement to first-time offenders with blood alcohol concentrations (BACs) below 0.15 percent ("first simple driving under the influence [DUI]") in June 2004.

Method: Trends in conviction types, interlock installation rates, and 2-year cumulative recidivism rates were examined for first-time convictions (simple, high-BAC, test refusal DUI; deferred prosecution; alcohol-related negligent driving) stemming from DUI arrests between January 1999 and June 2006.

Cell phone use while driving and attributable crash risk.

Objectives: Prior research has estimated that crash risk is 4 times higher when talking on a cell phone versus not talking. The objectives of this study were to estimate the extent to which drivers talk on cell phones while driving and to compute the implied annual number of crashes that could have been avoided if driver cell phone use were restricted.

Methods: A national survey of approximately 1200 U.

Perceptions and experiences of participants in a study of in-vehicle monitoring of teenage drivers.

Objectives: To assess the perceptions and experiences of participants in a study of a device that monitored teenagers' driving.

Methods: A device that continuously monitors and reports risky driving maneuvers was installed in vehicles of 84 newly licensed teenagers. Study groups varied by whether parents had access to a Web site that summarized their teenagers' driving and by whether in-vehicle alerts provided feedback to drivers.

Long-term effects of handheld cell phone laws on driver handheld cell phone use.

Objectives: As of October 2009, seven U.S. states and the District of Columbia (D.

Effect of enhanced seat belt reminders on driver fatality risk.

Objective: Enhanced seat belt reminders in automobiles have been shown to increase belt use rates by approximately 3 percentage points. The objective of this study was to estimate the effect of enhanced seat belt reminders on driver fatality risk.

Method: Data included all passenger vehicle driver deaths and vehicle registration counts in the United States for calendar years 2000-2007.

Effects of in-vehicle monitoring on the driving behavior of teenagers.

Objectives: The objective was to determine if teenage driving behavior improves when a monitoring and feedback device is installed in the teen's vehicle.

Methods: Vehicles of 85 teenage drivers were fit with a device that detected all instances of sudden braking/acceleration, speeding, and nonuse of seat belts. Drivers were assigned randomly to one of four research groups, differing in whether or not an alert sounded in the vehicle and whether or not parents were given access to websites containing notification records.

Relationship of dynamic seat ratings to real-world neck injury rates.

Objectives: The Insurance Institute for Highway Safety assigns consumer safety ratings to passenger vehicle seats based on laboratory sled tests that simulate rear-end collisions. The purpose of this research was to determine how well these ratings correlate to driver neck injury risk in real-world crashes.

Methods: Insurance claims for cars and SUVs struck in the rear by the front of another passenger vehicle were examined for evidence of driver neck injury.

Evaluation of automated speed enforcement in Montgomery County, Maryland.

Objectives: Almost one quarter of speeding-related fatalities occur on streets with speed limits of 35 mph or less. In 2007, Montgomery County, Maryland, implemented the state's first automated speed enforcement program, with camera use limited to residential streets with speeds limits of 35 mph or less and school zones. The purpose of the present study was to evaluate initial effects of camera enforcement on traffic speeds and to assess public attitudes.

Reducing red light running through longer yellow signal timing and red light camera enforcement: results of a field investigation.

Red light running is estimated to account for 900 intersection crash fatalities annually. Two principal methods used to reduce red light running involve lengthening the duration of yellow change intervals and automated red light enforcement. The present study evaluated the incremental effects on red light running of first lengthening yellow signal timing, followed by the introduction of red light cameras.

Trends over time in the risk of driver death: what if vehicle designs had not improved?

Objectives: Passenger vehicle driver death rates per million vehicle registrations declined steadily during calendar years 1985-2004. The present study sought to separate the effect of vehicle design changes from this trend.

Methods: Restricting the trend to a fixed set of model years removed the vehicle design effects, but there were still effects due to vehicle aging.

Effects of electronic stability control: an update.

Objective: An earlier study reported that electronic stability control (ESC) in passenger vehicles reduced single-vehicle crash involvement risk by 41% and single-vehicle fatal crash involvement risk by 56%. The purpose of the present study was to update these effectiveness estimates using an additional year of crash data and a larger set of vehicle models.

Methods: The amount of data increased by half, allowing for separate effectiveness estimates for cars and sport utility vehicles (SUVs) and a more detailed examination of multiple-vehicle crash types.

U.S. consumer crash test results and injury risk in police-reported crashes.

Consumer crash test programs provide comparative information on the crashworthiness of new vehicles which, in turn, should predict the performance of the same vehicles in real-world crashes. However, the detail and quality of available information from tests and real-world crashes differ widely, so identifying meaningful relationships between crash test results and real-world crashworthiness can be difficult. Despite these data limitations, studies in the late 1980s and mid-1990s reported positive correlations between dummy injury measures from the U.

Effects of head restraint and seat redesign on neck injury risk in rear-end crashes.

Automobile insurance claims were examined to determine the rates of neck injuries in rear-end crashes for vehicles with and without redesigned head restraints, redesigned seats, or both. Results indicate that the improved geometric fit of head restraints observed in many newer vehicle models are reducing the risk of whiplash injury substantially among female drivers (about 37% in the Ford Taurus and Mercury Sable), but have very little effect among male drivers. New seat designs, such as active head restraints that move upward and closer to drivers' heads during a rear impact, give added benefit, producing about a 43% reduction in whiplash injury claims (55% reduction among female drivers).

Effect on fatality risk of changing from secondary to primary seat belt enforcement.

Background: Most seat belt use laws originally passed in the United States contained language restricting enforcement to drivers already stopped for some other reason. States that have since removed this secondary enforcement restriction have reported increased seat belt use. The purpose of the present study was to estimate the effect of these law changes on driver fatality rates.

Relationships of frontal offset crash test results to real-world driver fatality rates.

In a study of the relationship between Insurance Institute for Highway Safety frontal offset crash test ratings and real-world fatality rates, there was a clear trend for better-rated vehicles to have lower driver fatality risk, although the correlation was not uniform across all vehicle groups or statistically significant in all cases. For all types of crashes combined, fatality rates per registered vehicle were generally lower for vehicles rated good than for vehicles rated poor, but rates for acceptable and marginal vehicles were not always within this range. A more precise examination of fatality risk was accomplished by comparing driver outcomes in fatal two-vehicle crashes.