U.S. Department of Transportation 1200 New Jersey Avenue SE., Washington, DC 20590

National Highway Traffic Safety Administration

Number 380 October 2009

Traffic Safety Facts

Traffic Tech – Technology Transfer Series

Identifying Situations Associated With Older 

Drivers’ Crashes

Previous research has highlighted a number of situations 

that pose particular difficulty for older drivers. Specific driving maneuvers that have been problematic for this population include left turns across traffic, high-speed roads, lane 

changes, and navigating intersections. 

This report extends previous findings by analyzing national 

crash data to identify driver, vehicle, roadway, and environmental characteristics associated with increased crash 

involvement by older drivers. The findings will be useful 

in developing countermeasures to improve safety of older 

drivers.

Methods

This study used 2002-2006 data from the Fatality Analysis 

Reporting System (FARS) and National Automotive Sampling System (NASS) General Estimates System (GES). For 

both the FARS and GES data, the analyses were restricted 

to single-vehicle and two-vehicle crashes involving passenger cars, sport utility vehicles, light vans, pickups, and other 

light trucks. 

Separate descriptive analyses of single-vehicle and two-vehicle crashes, using FARS and GES data, identified characteristics that most strongly represented crashes involving older 

drivers. The age groups of interest in these analyses were 

60-69, 70-79, and 80+. The analyses identified characteristics of the driver, vehicle, roadway/environment, and crash 

in which older drivers were overrepresented or underrepresented compared to other age groups. 

A limitation of the descriptive analysis is that both exposure 

to particular driving situations and “increased risk” may 

contribute to observed differences among age groups. To 

address this limitation, the researchers performed more indepth induced exposure analyses for the two-vehicle crashes. 

These analyses compared crash involvement ratios across 

driver age groups. Crash involvement ratios were defined as 

the proportion of at-fault crashes versus not-at-fault crashes 

for an age category. This approach assumes that the not-atfault drivers represent the exposure level of their age group 

in the driving situation under study, and therefore, controls 

for potentially different exposure levels across different age 

groups. 

Driver fault or responsibility for the crash was based on a 

driver’s contributing factors and/or violations. A driver was 

deemed at fault in the crash if one or more contributing factors or certain moving violations were present, and the other 

driver had no identified contributing factors or moving violations. Non-performance-related violations (e.g., driving 

with a suspended or revoked license) were not considered in 

determining fault. Two-vehicle crashes in which both drivers 

were deemed at fault or neither of the drivers was deemed at 

fault were excluded from the analysis. 

Results

Descriptive Analysis

As expected, the descriptive analyses of the FARS and GES 

data revealed that older drivers were overrepresented in certain types of crashes, while they were underrepresented in 

other types of crashes. Drivers 60 to 69 had crash rates similar to those of middle-aged drivers under most conditions. 

The oldest group of drivers, 80 and older, were overrepresented in overall crashes. This group generally differed from 

those 70 to 79 more in terms of degree of risk elevation, than 

in number of conditions under which risk was elevated. 

Left turns posed the greatest problem for older drivers. 

Twenty percent of two-vehicle crashes for drivers 70 to 79 

and 32% of two-vehicle crashes for drivers age 80 and above 

involved a left turn. In contrast, only 9% of two-vehicle 

crashes across drivers of all ages and 11% of two-vehicle 

crashes for drivers 60 to 69 involved a left turn.

In two-vehicle crashes, those 60 and older were more likely 

to be the struck vehicle (as opposed to the striking vehicle), to 

be involved in angle crashes, and to have received citations 

for failure to yield. This pattern of elevated risk increased 

with age. 

In single-vehicle crashes, drivers 60 and older were more 

likely to have been alone in the vehicle, more likely to crash 
into a parked car, and were less likely to have made a maneuver to avoid the collision, compared to drivers of all ages. 

Drivers 70 and older had elevated risk levels under additional conditions including driveways, alleys, and at intersections controlled by stop or yield signs. 

Older drivers were less likely than other drivers to be 

involved in certain types of crashes. Drivers 60 and older 

were less likely to be involved in alcohol-related, speedrelated, or nighttime crashes. Older drivers were less likely 

to be involved in crashes related to poor weather, such as rain 

or snow. 

Induced Exposure Analysis

The induced exposure analyses added further insight to these 

findings by providing the ratio of at-fault to not-at-fault drivers (the crash involvement ratio, or CIR) for various crash 

types for each age group. Values under 1.0 indicate a low 

rate of at-fault crashes, and values higher than 1.0 represent a 

high rate of at-fault crashes. Overall, FARS data indicate that 

drivers 60 to 69 had a CIR of 0.75, indicating a below-average 

risk of being found at fault in a crash. This risk increased to 

1.75 for drivers 70 to 79, and to 4.0 for those 80 and older (see 

Figure 1). 

Figure 1: Two-Vehicle Fatal CIRs by Driver Age Group

Results based on GES data differed in that the increase in 

CIR with age was less extreme. The CIR for the 60-to-69 age 

group was similar to that for the FARS data at 0.73. The overall values were 1.14 for drivers 70 to 79 and 1.91 for those age 

80 and older. While these scores are higher than 1.0, they are 

well below those based on the FARS data. The results suggest that at least some of the increase in crash risk seen in the 

FARS analyses may result from older adults’ increased risk 

of dying in a crash. 

Both the FARS and GES analyses demonstrated that drivers 60 to 69 managed most traffic situations nearly as well 

as their middle-aged counterparts. CIRs increased somewhat 

for drivers 70 to 79 under complex driving conditions such as 

navigating higher speeds, multiple lane roadways, and junctions. The oldest group, 80 and older, generally had substantially higher CIRs under a variety of conditions, including 

various intersection types (see Figure 2). Drivers 80 and older 

were especially vulnerable to right-side impacts, a situation 

that can occur when turning left at a stop sign. One of the 

most risky situations for older drivers was turning left at a 

signal-controlled intersection. 

Figure 2: Two-Vehicle CIRs for Police-Reported Crashes by 

Traffic Control Device

Discussion

Across this entire set of analyses there is little evidence of elevated risk for drivers 60 to 69. Most often, the data only begin 

to demonstrate a substantial upturn in crashes for drivers 70 

to 79, with overrepresentation for many crash types then 

accelerating more sharply for drivers 80 and older. 

How to Order

Download a copy of Identifying Behaviors and Situations 

Associated with Increased Crash Risk for Older Drivers (46 

pages plus appendices) from www.nhtsa.gov, or write to 

the Office of Behavioral Safety Research, NHTSA, NTI-130, 

1200 New Jersey Avenue SE., Washington, DC 20590, fax 

202-366-7394. Dr. Kathy Sifrit was the NHTSA Task Order 

Manager on this project.

TRAFFIC TECH is a publication to disseminate information about 

traffic safety programs, including evaluations, innovative programs, and new publications. Feel free to copy it as you wish. If you 

would like to receive a copy, contact Angela H. Eichelberger, Ph.D., 

Editor, fax 202-366-7394, e-mail: angela.eichelberger@dot.gov.

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1200 New Jersey Avenue SE., NTI-132

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