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Little is known about how state-level driver licensure laws, such as in-person renewal, vision tests, road tests, and the frequency of license renewal relate to the older driver traffic fatality rate. To determine whether state driver's license renewal policies are associated with the fatality rate among elderly drivers. Retrospective, longitudinal study conducted January 1990 through December 2000 of all fatal crashes in the contiguous United States identified in the Fatality Analysis Reporting System, which involved either an older (ages 65-74 years, 75-84 years, and > or =85 years) or middle-aged (ages 25-64 years) driver. Two regression approaches were used to study the effect of state laws mandating in-person renewal, vision tests, road tests, and frequency of license renewal on driver fatalities, controlling for state-level factors including the number of licensed elderly drivers, primary and secondary seatbelt laws, maximum speed limit laws, blood alcohol level of 0.08, and administrative license revocation drinking and driving laws, per capita income, and unemployment rate. The first regression approach examined only elderly driver fatalities and the second approach examined daytime elderly driver fatalities and used daytime fatalities among middle-aged drivers as a general control for unobserved variation across states and over time. Older driver fatalities and older and middle-aged daytime driver fatalities. Among individuals aged 85 years or older, there were a total of 4605 driver fatalities and 4179 daytime driver fatalities during the study period. For this age cohort, after controlling for middle-aged daytime driver deaths, states with in-person license renewal were associated with a lower driver fatality rate (incident rate ratio [RR], 0.83; 95% confidence interval [CI], 0.72-0.96). This was the only policy related to older drivers that was significantly associated with a lower fatality risk across both regression models. Thus, state-mandated vision tests, road tests, more frequent license renewal, and in-person renewal (for individuals aged 65-74 years and 75-84 years) were not found to be independently associated with the fatality rate among older drivers in the 2 models. In-person license renewal was related to a significantly lower fatality rate among the oldest old drivers. More stringent state licensure policies such as vision tests, road tests, and more frequent license renewal cycles were not independently associated with additional benefits.
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ORIGINAL CONTRIBUTION
Elderly Licensure Laws
and Motor V ehicle Fatalities
David C. Grabowski, PhD
Christine M. Campbell, AB
Michael A. Morrisey, PhD
M
OTOR VEHICLE FATALITY
rates among older driv-
ers have been increasing
since 1980, particularly
among those aged 85 years or older.
1
Moreover, elderly individuals have more
fatal crashes per mile driven than any
other group except teenage males.
2
The
aging of the US population over the next
25 years makes these statistics particu-
larly distressing. According to the Insur-
ance Institute for Highway Safety: “Driv-
ers aged 65 and older...areexpected
to account for as much as 25 percent of
total driver fatalities in 2030, compared
to 14 percent currently.”
3
Although there
is debate among clinicians about the ap-
propriate role of public policy in regu-
lating older drivers,
4,5
the American
Medical Association recently released a
report calling on physicians to help older
motorists drive more safely by testing
motor skills and by regulating medica-
tions.
6
Growing public concern over this
issue is reflected in newspaper editori-
als calling for stricter licensure laws
among the elderly.
7-9
State governments have a variety of
methods for increasing the stringency
of the licensure process for elderly in-
dividuals, including the adoption of in-
person renewal requirements, vision
tests, road tests, and the implementa-
tion of a shorter renewal period. To our
knowledge, there is no study that ex-
amines the relationship of these 4 fea-
tures of licensure laws with elderly
driver fatalities using recent data.
10-12
Therefore, we conducted a retrospec-
tive, longitudinal study using recent
data of all fatal crashes in the contigu-
ous United States to provide a compre-
hensive examination of the relation-
ship between licensure laws and safety
among elderly drivers.
METHODS
Study Population
This study uses motor vehicle fatality
information from the 1990 through
2000 Fatality Analysis Reporting Sys-
tem (FARS). FARS, which is collected
by the National Highway Traffic Safety
Administration, is a census of all mo-
tor vehicle crashes on a trafficway cus-
Author Affiliations: Lister Hill Center for Health Policy
(Drs Grabowski and Morrisey and Ms Campbell), De-
partment of Health Care Organization and Policy (Drs
Grabowski and Morrisey), School of Public Health, Uni-
versity of Alabama, Birmingham (Drs Grabowski and
Morrisey and Ms Campbell).
Corresponding Author: David C. Grabowski, PhD, De-
partment of Health Care Organization and Policy,
RPHB 330, 1665 University Blvd, Birmingham, AL
35294 (grabowsk@uab.edu).
Context Little is known about how state-level driver licensure laws, such as in-
person renewal, vision tests, road tests, and the frequency of license renewal relate to
the older driver traffic fatality rate.
Objective To determine whether state driver’s license renewal policies are associ-
ated with the fatality rate among elderly drivers.
Design, Setting, and Population Retrospective, longitudinal study conducted Janu-
ary 1990 through December 2000 of all fatal crashes in the contiguous United States
identified in the Fatality Analysis Reporting System, which involved either an older (ages
65-74 years, 75-84 years, and 85 years) or middle-aged (ages 25-64 years) driver.
Two regression approaches were used to study the effect of state laws mandating in-
person renewal, vision tests, road tests, and frequency of license renewal on driver
fatalities, controlling for state-level factors including the number of licensed elderly
drivers, primary and secondary seatbelt laws, maximum speed limit laws, blood alco-
hol level of 0.08, and administrative license revocation drinking and driving laws, per
capita income, and unemployment rate. The first regression approach examined only
elderly driver fatalities and the second approach examined daytime elderly driver fa-
talities and used daytime fatalities among middle-aged drivers as a general control for
unobserved variation across states and over time.
Main Outcome Measures Older driver fatalities and older and middle-aged day-
time driver fatalities.
Results Among individuals aged 85 years or older, there were a total of 4605 driver
fatalities and 4179 daytime driver fatalities during the study period. For this age cohort,
after controlling for middle-aged daytime driver deaths, states with in-person license re-
newal were associated with a lower driver fatality rate (incident rate ratio [RR], 0.83; 95%
confidence interval [CI], 0.72-0.96). This was the only policy related to older drivers that
was significantly associated with a lower fatality risk across both regression models. Thus,
state-mandated vision tests, road tests, more frequent license renewal, and in-person re-
newal (for individuals aged 65-74 years and 75-84 years) were not found to be inde-
pendently associated with the fatality rate among older drivers in the 2 models.
Conclusions In-person license renewal was related to a significantly lower fatality
rate among the oldest old drivers. More stringent state licensure policies such as vi-
sion tests, road tests, and more frequent license renewal cycles were not indepen-
dently associated with additional benefits.
JAMA. 2004;291:2840-2846 www.jama.com
2840 JAMA, June 16, 2004—Vol 291, No. 23 (Reprinted) ©2004 American Medical Association. All rights reserved.
tomarily open to the public that re-
sulted in the death of a person within
30 days of the crash.
13
FARS contains
detailed information on the vehicles,
drivers, occupants, and nonoccupants
involved in the crash. We construct age,
state, and year-specific fatality counts
from FARS. The 11 years of FARS data
encompass a total of 74428 driver fa-
talities among individuals aged 65 years
or older within the contiguous United
States, excluding Washington, DC.
However, to ascertain the effects of cer-
tain motor vehicle licensure laws on
older drivers, we also include a com-
parison group of all fatal crashes in-
volving drivers aged 25 to 64 years.
There were 231488 fatalities for this co-
hort during the study period. State-
year is the unit of analysis; there were
528 observations (48 states 11 years)
in the complete dataset.
Data on motor vehicle laws and their
dates of enactment were obtained from
several sources. We began with com-
pilations of laws from the Insurance In-
stitute for Highway Safety.
14
We then
conducted a telephone survey of all state
departments of motor vehicles to con-
firm the laws, resolve inconsistencies,
and obtain the dates of changes in the
laws. In several instances, we used codes
of annotated state statutes and spe-
cific legislative acts available on the In-
ternet to determine when laws were
implemented.
Annual state unemployment rate data
and information on the consumer price
index were obtained from the US Bu-
reau of Labor Statistics.
15,16
Annual per
capita income data were collected from
the US Bureau of Economic Analysis
and adjusted for inflation using the con-
sumer price index.
17
Data on the num-
ber of licensed drivers by age group,
state, and year were collected by the
Federal Highway Administration and
compiled in multiple editions of High-
way Statistics.
18
Study Variables
The number of overall and daytime (7
AM to 7 PM) driver fatalities were com-
puted by age cohort for each year in each
state. Separate computations were made
for drivers aged 25 to 64 years, 65 to 74
years, 75 to 84 years, and 85 years or
older.
Both the specific licensing require-
ments and the length of the renewal pe-
riod may be related to older driver
safety. The first binary variable mea-
sures whether a state has in-person re-
newal. In 2000, 45 states were in this
category. The other 2 binary licensure
variables measure whether the state
used vision or road tests at the time of
license renewal. In 2000, 40 states re-
quired vision testing for older drivers
renewing their licenses and 2 states re-
quired road tests. Importantly, the in-
person renewal, vision, and road tests
are not mutually exclusive categories.
Each binary variable captures the in-
dependent effect of the particular policy
on the traffic fatality rate holding the
other 2 policies constant. These laws are
expected to have meaningful effects in
reducing fatalities among older driv-
ers because they either demonstrate im-
paired driving ability, as in the case of
vision and road tests, or they provide
an opportunity for the license exam-
iner to observe potentially impaired
drivers, as in the case of in-person re-
newals. Since 1990, there has been only
minimal change in these laws within
states over time.
The frequency of the driver’s li-
cense renewal cycle was measured in
years; the average renewal cycle in 2000
was 4.35 years. Two states have short-
ened the period of renewal for older
drivers since 1990 and 3 states have
lengthened the renewal period for
younger drivers, but not for older driv-
ers. In 2000, 36 of the 48 contiguous
states used the same renewal provi-
sions for middle-aged and elderly driv-
ers and 14 states lengthened the re-
newal period for all adult drivers
between 1990 and 2000. A longer pe-
riod between license renewals is ex-
pected to increase fatalities. The longer
interval is hypothesized to reduce the
opportunity for license officials to ob-
serve the physical and mental condi-
tion of older license applicants whose
abilities may rapidly decline over time.
Additionally, a more frequent interval
may discourage some older drivers from
attempting to renew their license.
There are 6 other motor vehicle
laws that may affect fatalities among
older drivers that we include as covar-
iates in the model, which are mea-
sured as state-year specific dichoto-
mous variables.
10,19-21
First, primary enforcement of man-
datory seatbelt laws allows the police
to stop vehicles solely for belt-law vio-
lations; 16 states had such laws in 2000.
Second, secondary enforcement of seat-
belt laws allows police to issue a ticket
for a seatbelt violation, but only if there
was another infraction; by 2000, 31
states had enacted such laws. Third,
states have had the option to increase
the maximum speed limit to 65 mph on
rural interstate highways since 1987. In
1995, Congress repealed federal legis-
lation limiting speed limits. In 2000, 19
states had a rural speed limit of 65 mph
on rural interstates. Fourth, 29 states
had a rural speed limit of 70 mph or
higher on rural interstates in 2000.
Fifth, by 1988, all states except Mas-
sachusetts had per se laws that made
it a crime to drive with a blood alco-
hol level above 0.10. Between 1988 and
2000, 14 states lowered the legal thresh-
old from 0.10 to 0.08. In 2000, Con-
gress made the lower level the na-
tional standard. Sixth, in 2000, 39 states
had administrative license suspension
in which a driver’s license may be taken
before a conviction if a driver’s blood
alcohol level exceeds 0.08 or if the
driver refuses to take the test.
Earlier studies of motor vehicle fa-
talities report the importance of con-
trolling for the state of the economy.
22,23
Thus, the inflation-adjusted mean per
capita income and the unemployment
rate are included for each state-year
observation.
The number of licensed drivers was
reported by state and year for each of
the age cohorts. For the period 1990
through 1993, there were 40 missing
state-year observations for the cohort
aged 75 to 84 years and 69 missing
observations for the cohort aged 85
years or older. This variable was the
only source of missing data in this
MOTOR VEHICLE FATALITIES AMONG THE ELDERLY
©2004 American Medical Association. All rights reserved. (Reprinted) JAMA, June 16, 2004—Vol 291, No. 23 2841
study. The natural log of age-specific
licensed drivers is included as a mea-
sure of exposure in the multivariate
model. T
ABLE 1 reports the means
and SDs of the variables used in our
analysis for 2000. T
ABLE 2 summa-
rizes the number of state-year obser-
vations for which the various state
laws were applicable to older drivers
during the study period.
Of a total of 528 state-years in the data
set, in-person renewal was in effect for
495 state-years, vision tests were in effect
for 440 state-years, and road tests were
in effect for 22 state-years. The 65 mph
speed limit was in effect for 344 state-
years; 70 mph or higher speed limit, 131
state-years; primary enforcement of seat-
belt laws, 122 state-years; secondary en-
forcement of seatbelt laws, 357 state-
years; blood alcohol level of 0.08, 111
state-years; and administrative license re-
vocation, 371 state-years.
Statistical Analysis
The relationship of licensure laws and
fatalities was examined using 2 sepa-
rate estimation strategies. First, the
effect of licensure laws on the number
of elderly driver fatalities for the 3 older
age cohorts (65-74 years, 75-84 years,
85 years) was examined in a multi-
variate regression framework, control-
ling for the other state laws, macroeco-
nomic factors, and the number of
age-specific licensed drivers.
The second estimation strategy rec-
ognizes that these other covariates
included in the first multivariate speci-
fication may not adequately control for
unobserved state-level factors that may
be correlated with both elderly licen-
sure laws and traffic fatalities. For
instance, the degree of state law enforce-
ment may be correlated with both the
stringency of elderly licensure laws and
the number of traffic fatalities. Thus, we
use an alternate specification that relies
on comparing the gap in fatalities
between older and middle-aged driv-
ers in states with and without these laws.
This approach has been used in other
contexts including the labor market
effects of mandated maternity benefits
and the effects of the minimum legal
drinking age on teen childbearing.
24,25
The model assumes that middle-aged
drivers should be subject to the same
unobserved state-specific factors as
older drivers (eg, the presence of law
enforcement), but road tests, vision
tests, in-person renewal, and the
renewal frequency are predominantly
important for the safety of the older age
cohorts because of the frequency of
detecting impairment is likely to be
small for the middle-aged cohort.
Because the majority of driver fatalities
among older adults occur during day-
light hours, we restrict the model to
fatalities among older and middle-aged
adults that occur between the hours of
7
AM and 7 PM. Thus, by comparing the
differential effect of these laws on older
relative to middle-aged daytime drivers
in the state, we account for unobserved
state-level factors in estimating the rela-
tionship between licensure laws and
driver safety among the elderly.
Table 1. State-Level Descriptive Statistics for 2000 (N = 48)
Statistic Value
Motor vehicle fatalities by age of driver, mean (SD)
Total
25-64 y 315.23 (285.06)
65-74 y 36.38 (32.81)
75-84 y 34.60 (30.24)
85 y 11.90 (11.39)
Daytime
25-64 y 149.33 (128.27)
65-74 y 27.98 (24.24)
75-84 y 28.90 (25.44)
85 y 10.65 (10.32)
Licensed drivers by age, median (25%-75%)
25-64 y 1 997 700 (900 617-3 460 082)
65-74 y 235 067 (106 565-362 750)
75-84 y 136 552 (55 270-203 484)
85 y 30 896 (14 538-52 401)
Elderly licensure laws
In-person renewal, No. (%) 45 (0.94)
Vision test, No. (%) 40 (0.83)
Road test, No. (%) 2 (0.04)
Renewal period, mean (SD), y 4.35 (1.06)
Other state laws, No. (%) of states
Speed limit, mph
65 19 (0.40)
70 29 (0.60)
Seatbelt
Primary 16 (0.33)
Secondary 31 (0.65)
Blood alcohol level of 0.08 16 (0.33)
Administrative license suspension 39 (0.81)
Other, mean (SD)
Per capita income $16 226 ($2599)
Unemployment rate 3.84 (0.88)
Table 2. Number of State-Years That Policy
in Effect (1990-2000)
Law
No. of
State-Years
In-person renewal 495
Vision test 440
Road test 22
Speed limit, mph
65 344
70 131
Seatbelt
Primary 122
Secondary 357
Blood alcohol level of 0.08 111
Administrative license
suspension
371
Total
*
528
*
Total number of annual state-year observations for which
a policy was applicable to older drivers. The total sample
includes 11 annual observations for each of the 48 con-
tiguous states included in the study.
MOTOR VEHICLE FATALITIES AMONG THE ELDERLY
2842 JAMA, June 16, 2004—Vol 291, No. 23 (Reprinted) ©2004 American Medical Association. All rights reserved.
We implement this strategy by in-
cluding state-year observations repre-
senting both older and middle-aged
driver fatalities (ages 25-64 years)
within the regression model. Thus, the
complete data set includes 1056 obser-
vations (ie, 11 years 48 states 2 age
groups). The statistical test is accom-
plished by interacting the 4 state laws
with age-cohort dichotomous vari-
ables. It is the interaction of older age
and the presence of one of these laws
that measures the estimated addi-
tional impact on older drivers relative
to middle-aged ones.
It should be noted that this approach
assumes that the same factors influ-
ence daytime traffic fatality rates among
both middle-aged and older adults in a
given state and year. The first specifica-
tion, which includes state-year obser-
vations from the elderly age cohorts only
may actually be preferable. There is little
basis for distinguishing the approaches
a priori. Therefore, the models are best
viewed as complementary approaches
for exploring the validity of this study’s
key findings.
To account for zero values in some
state-year traffic fatality observations for
the older age categories, all the equa-
tions are estimated as count models us-
ing negative binomial models. We used
STATA regression statistical software
(version 8.0, STATA Corp, College Sta-
tion, Tex). Because of the likely pres-
ence of heteroskedasticity in the
grouped state-year data, the Huber-
White estimator was used to obtain ro-
bust SEs.
26
RESULTS
T
ABLE 3 contains results from the first
multivariate specification examining the
relationship of licensure laws and the
elderly driver fatality rate. In this model,
only 2 statistically significant findings
emerge across the 3 age cohorts. First,
those states with a law mandating in-
person renewal were associated with a
lower fatality rate for drivers aged 85
years or older relative to states with-
out in-person renewal (incident rate ra-
tio [RR], 0.83; 95% confidence inter-
val [CI], 0.71-0.96). During the study
period, there were 4605 total driver fa-
talities within this age cohort. Second,
those states with vision tests laws were
associated with a lower (incident RR,
0.92; 95% CI, 0.85-0.99) fatality rate for
drivers aged 65 to 74 years relative to
states without vision test laws. During
the study period, there were 19688 total
driver deaths within this age cohort.
Road test laws and the state-mandated
length of the renewal period were not
independently associated with fatali-
ties in any of the 3 age cohorts.
T
ABLE 4 contains results from the sec-
ond multivariate specification, which ac-
counts for omitted variables by exploit-
ing variation in daytime fatality rates
among middle-aged drivers across states.
Once again, a state law mandating in-
person renewal was associated with a
lower driver fatality rate for those aged
85 years or older compared with those
aged 25 to 64 years (incident RR, 0.83;
95% CI, 0.72-0.96). This result is based
on 4179 daytime driver deaths within
this age cohort. However, a state law
mandating in-person renewal was not
significantly associated with the fatal-
ity rate for the 2 other age cohorts. State
laws pertaining to vision tests, road tests,
and the length of the renewal period
were not statistically associated with the
fatality rate among older drivers for any
of the 3 age cohorts.
COMMENT
This study represents the first compre-
hensive analysis of licensure laws and
the fatality rate among older drivers us-
ing recent national data. Across 2 al-
ternative multivariate specifications,
states with in-person license renewal
were found to be associated with a lower
driver fatality rate for the cohort aged
85 years or older. The estimates from
the 2 model specifications were remark-
ably similar. That is, the relative inci-
dence rate for states with in-person li-
cense renewal was roughly 17% lower
than those states with no in-person re-
newal. However, in-person renewal was
not associated with a lower fatality rate
among the 2 relatively younger co-
horts. Moreover, taken together, our 2
alternative estimation strategies indi-
cated that state laws mandating vision
tests, road tests, and more frequent re-
newals were not associated with a lower
Table 3. Association of Licensure Laws With Older Adult Driver Fatalities
Total No. of Deaths
Among Older Drivers
Adjusted
Incident RR (95% CI)
*
States
With Law
States
Without Law
Age 65-74 y (528 state-years)
In-person renewal 18 186 1502 1.05 (0.95-1.16)
Vision test 16 454 3234 0.92 (0.85-0.99)
Road tests 720 18 968 1.09 (0.97-1.21)
Renewal period, y† NA NA 1.01 (0.99-1.03)
Age 75-84 y (488 state-years)
In-person renewal 15 000 1297 0.95 (0.86-1.05)
Vision test 13 678 2619 0.95 (0.87-1.04)
Road tests 621 15 676 0.98 (0.87-1.12)
Renewal period, y† NA NA 1.01 (0.98-1.03)
Age 85 y (459 state-years)
In-person renewal 4275 330 0.83 (0.71-0.96)
Vision test 3911 694 1.07 (0.95-1.20)
Road tests 142 4463 1.01 (0.79-1.28)
Renewal period, y† NA NA 1.02 (0.99-1.05)
Abbreviations: CI, confidence interval; NA, not applicable; RR, rate ratio.
*
Adjusted for the natural log of licensed drivers in the given age cohort, the state unemployment rate, the real per
capita state income, and binary indicators for primary seatbelt, secondary seatbelt, 65 mph rural speed limit, 70 mph
or higher rural speed limit, blood alcohol level of 0.08, and administrative license suspension laws, and year dummy
variables. Models are estimated using negative binomial regression. Each regression includes state and year cells
representing the older age group (65-74 years, 75-84 years, or 85 years). The dependent variable is the count of
fatalities in the given age group. The CI was constructed using Huber-White adjusted SEs.
†Based on the increment of 1 year.
MOTOR VEHICLE FATALITIES AMONG THE ELDERLY
©2004 American Medical Association. All rights reserved. (Reprinted) JAMA, June 16, 2004—Vol 291, No. 23 2843
fatality rate among older drivers. Thus,
the bottom line from this study is that
in-person renewal is associated with a
lower fatality rate among the oldest old
drivers, but vision tests, road tests, and
more frequent renewals are not inde-
pendently associated with additional
safety benefits.
This study cannot address the exact
mechanism by which in-person license
renewal is related to the fatality rate
among elderly drivers (aged 85 years),
but we can speculate on 2 causal path-
ways. Both hypotheses stem from pre-
vious research that has found that states
with more stringent license renewal re-
quirements are associated with lower
rates of licensed elderly drivers.
27
First,
in-person renewal requirements pro-
vide an opportunity for license inspec-
tors to either refuse to grant licenses to
obviously impaired drivers or to refer
such persons for medical evaluation
prior to receiving a new license. Thus,
it may be the case that greater numbers
of potentially unsafe older drivers are de-
tected and refused a license within the
in-person renewal process.
Given this explanation, one may ex-
pect state laws mandating vision and
road tests to be associated with addi-
tional safety gains independent of in-
person license renewal, but our find-
ings did not support such a relationship.
Recent research has argued that vision
acuity is only weakly related to crash
involvement.
28
Thus, the vision acuity
tests used by most states in the license
renewal process may not detect addi-
tional unsafe drivers relative to in-
person renewal without such a vision
test requirement. However, it is impor-
tant to note that in-person renewal al-
lows driver license examiners the op-
portunity to refer certain older drivers
for medical evaluation, and some of
these evaluations may include more so-
phisticated testing such as neurologi-
cal examinations, comprehensive vi-
sual examinations, simulator tests, and
road tests. Thus, it would be a mistake
to conclude based on our results that
there is never a benefit to a compre-
hensive medical evaluation. On an in-
dividual basis, these evaluations may be
important toward identifying poten-
tially unsafe drivers. However, our in-
terpretation of the findings is that in-
person license renewal effectively
captures the “going to the department
of motor vehicles” phenomenon and
that state laws mandating vision and
road tests for all older drivers do not
offer independent benefits toward low-
ering the fatal crash rate among older
drivers.
A second hypothesis consistent with
our findings is that potentially unsafe
older drivers may be less likely to re-
apply for a license when facing in-
person renewal. That is, potentially un-
safe older adults may recognize the low
likelihood of relicensure and forego the
license renewal process altogether. Un-
fortunately, state-level data on the num-
ber of elderly applicants for licenses are
not available nationally over time, but
this explanation would fit into the
broader literature showing that older
drivers impose many restrictions on
their own driving behavior. For ex-
ample, older drivers have been found
to limit driving at night, in poor
weather, on highways, during rush
hour, and following at-fault crashes.
29
Moreover, other research has shown
that older adults limit their driving with
early changes in their spatial vision
function and depth perception.
30
In the
broad continuum of driving behav-
iors, the self-restriction of driving may
culminate in the cessation of driving al-
together. Although we cannot test this
relationship directly with our current
data, an in-person license renewal re-
quirement may serve as a deterrent to
relicensure for potentially unsafe el-
derly drivers.
Our findings differ in some respects
from the earlier literature on licensure
laws and older driver fatalities. In con-
trast to our findings, the existing lit-
erature has generally argued that vi-
sion tests are associated with lower
elderly driver fatality rates. In a multi-
variate study of the national FARS data
for the 5-year period (1985-1989) di-
rectly preceding our study period, Levy
et al
2
found that state-mandated tests
of visual acuity were associated with a
lower fatal crash risk for elderly driv-
Table 4. Association of Licensure Laws With Daytime Driver Fatalities
Total Older Driver
Daytime Deaths
Adjusted
Incident RR (95% CI)
*
States
With Law
States
Without Law
Age 65-74 y (1056 state-years)
In-person renewal 13 995 1157 1.06 (0.96-1.16)
Vision tests 12 661 2491 0.94 (0.87-1.02)
Road tests 540 14 612 1.08 (0.96-1.22)
Renewal period, y† NA NA 1.00 (0.98-1.03)
Age 75-84 y (976 state-years)
In-person renewal 12 767 1126 0.93 (0.84-1.02)
Vision tests 11 636 2257 0.98 (0.89-1.07)
Road tests 545 13 348 1.13 (1.00-1.27)
Renewal period, y† NA NA 1.00 (0.98-1.03)
Age 85 y (918 state-years)
In-person renewal 3869 310 0.83 (0.72-0.96)
Vision tests 3535 644 1.07 (0.94-1.21)
Road tests 127 4052 1.10 (0.87-1.40)
Renewal period, y† NA NA 1.02 (0.98-1.05)
Abbreviations: CI, confidence interval; NA, not applicable; RR, rate ratio.
*
Adjusted for the natural log of licensed drivers in the given age cohort, the state unemployment rate, the real per
capita state income, and binary indicators for primary seatbelt, secondary seatbelt, 65 mph rural speed limit, 70 mph
or higher rural speed limit, blood alcohol level of 0.08, and administrative license suspension laws, and year and age
cohort dummy variables. Models are estimated using negative binomial regression. Each regression includes state
and year cells representing both a middle-aged (25-64 years) and older age group (65-74 years, 75-84 years, or
85 years). The dependent variable is the count of fatalities in the given age group. The CI was constructed using
Huber-White adjusted SEs.
†Based on the increment of 1 year.
MOTOR VEHICLE FATALITIES AMONG THE ELDERLY
2844 JAMA, June 16, 2004—Vol 291, No. 23 (Reprinted) ©2004 American Medical Association. All rights reserved.
ers aged 70 years or older. In a multi-
variate study of FARS data for the pe-
riod 1989 through 1991, Shipp
12
found
that vision test laws were significantly
associated with lower vehicle occu-
pant fatality rates among drivers aged
60 years or older. Finally, in a bivari-
ate study of FARS data from 20 states
for the period 1986 through 1988, Nel-
son et al
31
found that states with vi-
sion test laws were associated with a
lower fatal crash involvement rate for
drivers aged 65 years or older.
There are several explanations for the
different conclusions regarding vision
tests between our study and previous
work. First, we have specified our
model differently from earlier work by
separately examining the effects of in-
person license renewal and vision test
laws. The previous studies of vision test
laws have neglected to account for in-
person renewal by grouping all states
without vision test laws together in the
control group, regardless of whether the
state had in-person license renewal or
not. In 2000 for example, 5 states had
in-person renewal requirements with-
out mandating vision tests. Thus, the
negative association we observe be-
tween in-person renewal and the driver
fatality rate among the elderly in our
study may have been misattributed to
vision test laws in earlier studies.
Our multivariate estimates also dif-
fer from the earlier literature in several
other significant ways. Our data are more
recent (1990-2000) than the other stud-
ies. Other investigators generally exam-
ined data from the 1980s and early 1990s.
Given the trends toward increased licen-
sure rates and higher annual mileage
driven among older persons,
3
the ear-
lier data may be less relevant for today’s
elderly driving population. The inves-
tigators in earlier studies also did not con-
trol for state traffic laws unrelated to
licensure such as seatbelt, speed limit,
and alcohol-control laws. Our study is
the also first to recognize potential het-
erogeneity in the response to licensure
laws in the younger old and the older
old. Earlier work, which grouped all
elderly above a particular age together,
might have masked or distorted rela-
tionships within different elderly age
groups. For example, we found a statis-
tically significant relationship between
in-person license renewal and the elderly
driver fatality rate for the cohort aged 85
years or older, but no significant rela-
tionship among the cohort aged 65 to
74 years or the cohort aged 75 to 84
years.
A final distinction between this ar-
ticle and the earlier literature is the use
of the middle-aged daytime driver fa-
tality rate as a control for unobserved
variation in driving conditions across
states and over time. Because it is dif-
ficult to construct a fully specified
model due to data limitations, omit-
ted variable bias is always a concern
when modeling state motor vehicle
rates. Only 1 previous study in the lit-
erature explored a similar model speci-
fication as a (unreported) sensitivity
check to their main results.
2
Impor-
tantly, our main results remained es-
sentially stable when we introduced
middle-aged daytime drivers as a gen-
eral control within the model. This sen-
sitivity check supports the idea that un-
observed heterogeneity is not the
underlying source of our findings.
In regard to road test laws, previous
research generally supports our cur-
rent finding that these laws are not in-
dependently associated with lower fa-
tality rates among older adults. Levy et
al
2
found no significant association be-
tween road test laws and the driver fa-
tality rate among older adults. Simi-
larly, Rock
11
found that eliminating a
state law mandating road tests in Illi-
nois for drivers aged 69 to 74 years in
late 1989 did not increase the fatality
crash rate among elderly Illinois driv-
ers in this age group relative to a con-
trol group that experienced no change
in requirements. However, in contrast
to our findings, increasing the fre-
quency of renewal from 4 years to 2
years for those aged 81 to 86 years and
1 year for those aged 87 years or older
was found to significantly decrease the
fatality crash rate relative to the con-
trol group. One explanation for the dif-
ference in findings relative to our study
is that Illinois is one of the most strin-
gent states in terms of the frequency of
license renewal. By comparison, only
11% of the state-year observations in
our study had a renewal period of less
than 4 years. For those older drivers
with rapidly declining driving skills,
more frequent renewals may be neces-
sary to observe a significant decrease in
the fatality rate. Further work exam-
ining this issue is necessary.
The current study has limitations.
Some of the laws evaluated in this study,
such as road tests, have only been
implemented in a handful of states. This
makes it difficult to obtain precise es-
timates of their relationship with older
driver safety. In addition, little is known
about the degree of enforcement of the
license renewal tests across states and
over time. Moreover, we broadly clas-
sified states with and without vision test
laws without considering the level of
visual acuity required by states. In terms
of the FARS data, we can only mea-
sure the year of the fatal crash, not the
year in which the driver involved re-
newed his/her license. Although there
were few changes in state licensure laws
during our study, any changes during
the study (or in the years immediately
preceding the study) may have led us
to misclassify the state licensure laws
in effect at the time of license renewal.
Finally, FARS data only allow an in-
vestigation of fatalities; research also is
needed on the nonfatal consequences
of licensure laws for older drivers.
Across 2 different estimation strate-
gies, the results of this study support the
importance of in-person license re-
newal for older adults as a potential
mechanism toward decreasing the fa-
tality crash rate among the oldest old
drivers. However, more stringent state
licensure laws mandating vision tests,
road tests, and shorter renewal cycles
were not independently associated with
a decrease in the older driver fatality rate.
Author Contributions: Dr Grabowski had full access
to all of the data in the study and takes responsibility
for the integrity of the data and the accuracy of the
data analysis.
Study concept and design: Grabowski, Morrisey.
Acquisition of data: Grabowski, Morrisey.
Analysis and interpretation of data: Grabowski,
Campbell, Morrisey.
Drafting of the manuscript: Grabowski, Morrisey.
MOTOR VEHICLE FATALITIES AMONG THE ELDERLY
©2004 American Medical Association. All rights reserved. (Reprinted) JAMA, June 16, 2004—Vol 291, No. 23 2845
Critical revision of the manuscript for important in-
tellectual content: Grabowski, Campbell, Morrisey.
Statistical expertise:Grabowski, Morrisey.
Obtained funding: Grabowski, Morrisey.
Administrative, technical, or material support:
Campbell.
Supervision: Morrisey.
Funding/Support: This research was supported in part
by grant 01230 from the University Transportation
Center for Alabama and by grant R49/CCR403641
from the Centers for Disease Control and Preven-
tion, National Center for Injury Prevention and Con-
trol to the Injury Control Research Center at the Uni-
versity of Alabama at Birmingham.
Role of the Sponsor: Other than providing financial
support, the University Transportation Center for Ala-
bama and the Injury Control Research Center at the
University of Alabama, Birmingham, played no part
in the collection or analysis of these data or approval
of publication.
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MOTOR VEHICLE FATALITIES AMONG THE ELDERLY
2846 JAMA, June 16, 2004—Vol 291, No. 23 (Reprinted) ©2004 American Medical Association. All rights reserved.
... It may not be promising to further amend the operation of cognitive screening test results because a study revealed that older drivers who screened positive by the test reduced vehicle mileage and had a smaller risk of collisions per licensed driver than negative counterparts. 26 Many studies examined the associations between non-cognitive screening programs or licensing requirements for older drivers and the risk of road crashes, [27][28][29][30][31][32] and while some studies conclude that there is no clear benefit, 27,29,30 others suggest a positive effect. 28,31,32 Since no single screening tool is available to determine fitness to drive, it may be useful to develop a comprehensive screening tool evaluating vision, physical and cognitive functions, medical comorbidities, and medications and to provide older drivers with necessary support. ...
... 26 Many studies examined the associations between non-cognitive screening programs or licensing requirements for older drivers and the risk of road crashes, [27][28][29][30][31][32] and while some studies conclude that there is no clear benefit, 27,29,30 others suggest a positive effect. 28,31,32 Since no single screening tool is available to determine fitness to drive, it may be useful to develop a comprehensive screening tool evaluating vision, physical and cognitive functions, medical comorbidities, and medications and to provide older drivers with necessary support. 33 It should also be noted that such a screening might trigger driving cessation before older drivers were actually unsafe to drive. ...
Article
Background: We examined whether the policy amendment from March 2017 for a cognitive screening test for older drivers at driver's license renewal was associated with the decreased risk of motor vehicle collisions for drivers and the increased risk of injuries for pedestrians and cyclists among older people. Methods: This was a controlled interrupted time-series study. We used police-reported data on the number of collisions as drivers and injuries as pedestrians and cyclists among people aged 70 years or older in Japan from July 2012 to December 2019. As the outcome measures, we used the ratio of the monthly number of collisions per population among drivers of three groups aged 75 years or older (75-79, 80-84, and ≥85 years), who were targeted or exposed by the policy, to that among drivers aged 70 to 74 years, who were unaffected or unexposed by the policy and would serve as controls. The ratio of pedestrian and cyclist injuries was also calculated, as previous studies have shown a concomitant increase in these injuries after the introduction of cognitive screening for driver's licenses. Results: During the study period, there were 602,885 collisions as drivers and 196,889 injuries as pedestrians and cyclists among people aged 70 years or older. After the policy amendment in March 2017, collisions decreased among male drivers, and injuries increased among some age subgroups in both sexes. Cumulative estimated changes in the numbers of collisions and injuries from March 2017 to December 2019 were -3670 (95% confidence interval: -5125, -2104) and 959 (95% confidence interval: 24, 1834), respectively. Conclusions: Following the policy amendment, there was a decrease in motor vehicle collisions as drivers and an increase in road injuries as pedestrians and cyclists among older people.
... In-person renewal was found to be associated with lower fatality rates among older drivers (Morrisey & Grabowski, 2005), with one study suggesting that this was the only license renewal requirement that was "independently associated with additional benefits" to driver safety (Grabowski et al., 2004). Specifically, Tefft (2014) found a 31% reduction in the fatality rate among drivers 85 and older who were subjected to in-person renewal requirements. ...
Technical Report
Full-text available
This report, prepared by Washington State University’s (WSU) Division of Governmental Studies and Services (DGSS), was produced at the request of the Washington State Department of Licensing (DOL) to assist in addressing specific legislative requirements contained in Engrossed Substitute House Bill (ESHB) 1125 Section 208 3a, which called for the DOL “to develop a comprehensive plan aimed at improving older driver safety.” DGSS was contracted as an independent research unit to produce a plan for addressing the following: (1) a comprehensive review of DOL policies aimed to address issues related to older drivers as well as medically at-risk drivers; (2) feasibility analysis for establishing a medical advisory board (MAB) for the purpose of advising on policy surrounding medically at-risk drivers, to include policies for managing driving privileges; (3) a recommended assessment tool that can be used by the DOL to identify a driver’s level of risk to themselves or others; and (4) guidance on how each component of the comprehensive plan will balance the improvement of driver safety with the preservation of maximal driver independence and privacy. To develop a comprehensive plan for improving older driver safety, DGSS consulted with numerous entities as specified by ESHB 1125, including individuals representing the Washington Traffic Safety Commission, the Department of Health, the Elder Law Section of the Washington State Bar Association, organizations serving older drivers (e.g., AAA, AARP, Washington State Senior Citizens’ Lobby, Washington State Council on Aging), and driver rehabilitation specialists. In addition, DGSS conducted a comprehensive review of existing research to provide an assessment of the nature and scope of driver safety as it pertains to age; quantitatively analyzed Washington State crash data; assessed the feasibility of establishing a medical advisory board (MAB) in the state of Washington through evaluation of existing practices in the United States and review of the relevant research MABs; and reviewed existing screening tools and assessments for validity and reliability.
... All states represented in this study offer some form of remote license renewal without visual function being measured [17]. It has been suggested that such remote renewal processes may pose a public safety threat, as Grabowski et al. have reported that in-person renewal policies reduce MVC rates in older drivers [26]. ...
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Purpose of Review In this article, we review the current literature on glaucoma and its relationship to various visual functions, driving licensure, driving patterns and public safety. Recent Findings Drivers with glaucomatous vision impairment tend to be involved in a higher number of motor vehicle collisions and self-report more driving concerns and limitations than those without glaucoma, but not all studies agree entirely. This lack of agreement is reflected in inconsistencies regarding licensure standards throughout the United States and across the world. Many opinions exist regarding the best means of testing, training and licensing individuals with glaucoma with the aim of ensuring of public safety while also allowing for individual independence. Summary There is no consensus regarding just how much of a public safety threat glaucoma presents in the context of driving, and what specific visual function parameters contribute most to this potential threat. Continued work in this area will be imperative to understand this important, and growing, issue.
... The analysis found that stricter renewal requirements, including the on-road test, did show an association with reduced motor vehicle collisions (MVCs) per licensed driver (Thomas et al., 2013). This could be due to purging inactive drivers from the registry, but the in-person renewal requirement has consistently proved to have the largest impact on reducing MVCs and traffic fatalities among older drivers (Grabowski et al., 2004). Lack of direct evidence to support mandatory on-road testing for older adults should not be used to entirely discount the idea of age-based triggers for any kind of driving assessment. ...
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Background and Objectives Over 10,000 people a day turn 65 in the United States. For many older adults, driving represents an essential component of independence and is one of the most important factors in overall mobility. Recent survey studies in older adults suggest that up to 60% of older adult drivers with mild cognitive impairment, and up to 30% with dementia, continue to drive. The purpose of this review is to provide a comprehensive and detailed resource on the topics of cognition and driving for clinicians, researchers, and policymakers working on efforts related to older adult drivers. Research Design and Methods Publications on PubMed and Medline and discussions with experts working in geriatrics, technology, driving policy, psychology, and diverse aspects of driving performance were utilized to inform the current review. Results Research indicates that there is a complex and inverse correlation between multiple cognitive measures, driving performance, and risky driving behaviors. The fragmented nature of available peer-reviewed literature, and a reliance on correlative data, do not currently allow for the identification of the temporal and reciprocal nature of the interplay between cognition and driving endpoints. Discussion and Implications There are currently no widely accepted definitions, conceptual models, or uniform set of analyses for conducting geriatric research that is focused on driving. Establishing conventions for conducting research that harmonizes the fields of geriatrics, cognition, and driving research is critical for the development of the evidence base that will inform clinical practice and road safety policy.
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Objectives: Washington State implemented a new policy in 2004 that allowed drivers younger than 70 years old to renew their driver license by mail or online at every other renewal. Drivers aged 70 years and older were still required to renew in-person every 6 years. The purpose of this study was to evaluate whether this policy change was associated with motor vehicle crash (MVC) injury and fatality among drivers, non-drivers, and all road users aged 45-69 years. Methods: Controlled interrupted time series analysis models were fit to compare injury and fatality rates for these road users affected by the requirement to older road users not affected by the requirement (70 years and older). Differential level and slope changes in injury and fatality rates were used to estimate associations with the change in the license renewal requirement. Results: We did not find evidence that implementation of online driver license renewal in Washington was associated with increased injury or fatality rates among drivers, non-drivers, or all road users aged 45-69 years relative to those aged 70 years and older. Conclusions: Allowing driver license renewal online or by mail at every other renewal appears to be a safe strategy for less restrictive driver licensing for drivers aged 45-69 years. Future research should continue to evaluate the potential impacts of in-person and online renewal policies.
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Background Road Traffic injuries (RTI) are among the top ten leading causes of death in the world resulting in 1.35 million deaths every year, about 93% of which occur in low‐ and middle‐income countries (LMICs). Despite several global resolutions to reduce traffic injuries, they have continued to grow in many countries. Many high‐income countries have successfully reduced RTI by using a public health approach and implementing evidence‐based interventions. As many LMICs develop their highway infrastructure, adopting a similar scientific approach towards road safety is crucial. The evidence also needs to be evaluated to assess external validity because measures that have worked in high‐income countries may not translate equally well to other contexts. An evidence gap map for RTI is the first step towards understanding what evidence is available, from where, and the key gaps in knowledge. Objectives The objective of this evidence gap map (EGM) is to identify existing evidence from all effectiveness studies and systematic reviews related to road safety interventions. In addition, the EGM identifies gaps in evidence where new primary studies and systematic reviews could add value. This will help direct future research and discussions based on systematic evidence towards the approaches and interventions which are most effective in the road safety sector. This could enable the generation of evidence for informing policy at global, regional or national levels. Search Methods The EGM includes systematic reviews and impact evaluations assessing the effect of interventions for RTI reported in academic databases, organization websites, and grey literature sources. The studies were searched up to December 2019. Selection Criteria The interventions were divided into five broad categories: (a) human factors (e.g., enforcement or road user education), (b) road design, infrastructure and traffic control, (c) legal and institutional framework, (d) post‐crash pre‐hospital care, and (e) vehicle factors (except car design for occupant protection) and protective devices. Included studies reported two primary outcomes: fatal crashes and non‐fatal injury crashes; and four intermediate outcomes: change in use of seat belts, change in use of helmets, change in speed, and change in alcohol/drug use. Studies were excluded if they did not report injury or fatality as one of the outcomes. Data Collection and Analysis The EGM is presented in the form of a matrix with two primary dimensions: interventions (rows) and outcomes (columns). Additional dimensions are country income groups, region, quality level for systematic reviews, type of study design used (e.g., case‐control), type of road user studied (e.g., pedestrian, cyclists), age groups, and road type. The EGM is available online where the matrix of interventions and outcomes can be filtered by one or more dimensions. The webpage includes a bibliography of the selected studies and titles and abstracts available for preview. Quality appraisal for systematic reviews was conducted using a critical appraisal tool for systematic reviews, AMSTAR 2. Main Results The EGM identified 1859 studies of which 322 were systematic reviews, 7 were protocol studies and 1530 were impact evaluations. Some studies included more than one intervention, outcome, study method, or study region. The studies were distributed among intervention categories as: human factors (n = 771), road design, infrastructure and traffic control (n = 661), legal and institutional framework (n = 424), post‐crash pre‐hospital care (n = 118) and vehicle factors and protective devices (n = 111). Fatal crashes as outcomes were reported in 1414 records and non‐fatal injury crashes in 1252 records. Among the four intermediate outcomes, speed was most commonly reported (n = 298) followed by alcohol (n = 206), use of seatbelts (n = 167), and use of helmets (n = 66). Ninety‐six percent of the studies were reported from high‐income countries (HIC), 4.5% from upper‐middle‐income countries, and only 1.4% from lower‐middle and low‐income countries. There were 25 systematic reviews of high quality, 4 of moderate quality, and 293 of low quality. Authors' Conclusions The EGM shows that the distribution of available road safety evidence is skewed across the world. A vast majority of the literature is from HICs. In contrast, only a small fraction of the literature reports on the many LMICs that are fast expanding their road infrastructure, experiencing rapid changes in traffic patterns, and witnessing growth in road injuries. This bias in literature explains why many interventions that are of high importance in the context of LMICs remain poorly studied. Besides, many interventions that have been tested only in HICs may not work equally effectively in LMICs. Another important finding was that a large majority of systematic reviews are of low quality. The scarcity of evidence on many important interventions and lack of good quality evidence‐synthesis have significant implications for future road safety research and practice in LMICs. The EGM presented here will help identify priority areas for researchers, while directing practitioners and policy makers towards proven interventions.
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In 2011, Utah began requiring that drivers aged 65 years and older pass a vision test at each license renewal. This study aims to investigate if the mandatory vision test associated with motor vehicle fatality and injury rates in older road users. We fit controlled interrupted time series analysis models to compare fatality and injury rates for older adults (65+) affected by the law to younger adults (45–64) unaffected by the law. The models yielded estimates of differential level and slope changes in fatality and injury rates, which we used to estimate policy associations. We did not find evidence that implementing an accelerated vision test for older adults in Utah was associated with a reduction in injury or fatality rates among older (65+) drivers and non-drivers relative to those aged 45–64. Other strategies might be considered to prevent fatal MVCs in older adults.
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Given the importance of driving mobility for older adults in the United States, it is important to examine how license renewal policies are related to driving mobility and whether the driving mobility of older adults with health limitations may be especially affected by such policies. The present study examined the association between license renewal requirements and driving mobility in a national sample of 89,757 older adults aged 62 and older in the United States ( M age = 71.57, standard deviation age = 7.48). Using generalized estimating equations, the associations between two driver licensing requirements (in-person renewal and length of renewal cycle) and two indicators of driving mobility (driving status and annual driving mileage) were examined. Results indicated that in-person license renewal was significantly associated with lower driving mileage but not driving status. The association between in-person license renewal and lower driving mileage was greater for people who reported a health-related travel difficulty: in states requiring in-person license renewal, drivers with a health-related travel difficulty had driven 590 fewer miles in the previous year compared with drivers without such difficulties. Among people who experienced in-person license renewal requirements, a longer time between renewals was not significantly associated with driving status or annual mileage. The findings of the current study, combined with previous work showing a lack of safety benefits of in-person license renewal, suggest that in-person license renewal requirements may unnecessarily restrict the driving mobility of some older adults.
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In her second paper on vision and driving, Professor Joanne Wood summarises evidence for the impact of visual function on driving and reviews the legal driving standards.
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Purpose: This study aimed to determine what proportion of visually impaired patients continue driving despite falling short of the legal cutoffs described in state licensure laws. Methods: We created a driving habits survey and administered it to 335 consecutive adult low vision patients presenting for their initial evaluation at the Vanderbilt Eye Institute. We measured visual acuity and contrast sensitivity as part of the clinical evaluation and accounted for historic visual field results where indicated. We compared self-reported licensure and driving status against the vision criteria for licensure in each subject's home state. Results: Two hundred fifty-seven subjects (76.7%) possessed an unexpired license. One hundred forty-one (54.9%) of these demonstrated vision, which would meet their home state's licensure criteria. Ninety-five of 134 current drivers (70.9%) met their home state's licensure criteria. Thirty-nine current drivers (29.1%) were driving outside the bounds of licensure criteria in their state. Among licensed subjects, being a current driver was associated with younger age (P < .001), better visual acuity (P < .001), and better contrast sensitivity (P < .001). Conclusions: Many drivers do not possess adequate vision for licensure based on their home state's current standards. Changes to licensure qualification and renewal procedures may be advisable.
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This study presents panel-based evidence on the overall fatality consequences of recent speed-limit increases in the United States. The results suggest that higher speed limits had highly heterogeneous effects, generally increasing fatalities among women and the elderly but reducing them among males.
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Objectives Older drivers have become a larger part of the driving population and will continue to do so as the baby boomers reach retirement age. The purpose of this study was to identify the potential effects of this population increase on highway safety. Methods Driver involvement rates for all police reported crashes were calculated per capita, per licensed driver, and per vehicle-mile of travel for 1990 and 1995. Also, driver involvement rates for fatal crashes were calculated for 1983, 1990, and 1995. Based on current crash rates per licensed driver and estimates of the future number of licensed drivers, projections of crashes involving drivers aged 65 and older were made for years 2010, 2020, and 2030. Results Driver crash involvement rates per capita decreased with age, but fatal involvement rates per capita increased starting at age 70. The same pattern existed for involvement rates per licensed driver. For both all crashes and fatal crashes, involvement rates per mile driven increased appreciably at age 70. Using projections of population growth, it was estimated that for all ages there will be a 34% increase in the number of drivers involved in police reported crashes and a 39% increase in the number involved in fatal crashes between 1999 and 2030. In contrast, among older drivers, police reported crash involvements are expected to increase by 178% and fatal involvements may increase by 155% by 2030. Drivers aged 65 and older will account for more than half of the total increase in fatal crashes and about 40% of the expected increase in all crash involvements; they are expected to account for as much as 25% of total driver fatalities in 2030, compared with 14% presently. Conclusions By most measures, older drivers are at less risk of being involved in police reported crashes but at higher risk of being in fatal crashes. Although any projections of future crash counts have inherent uncertainty, there is strong evidence that older drivers will make up a substantially larger proportion of drivers involved in fatal crashes by 2030 because of future increases in the proportion of the population aged 65 and older, and trends toward increased licensure rates and higher annual mileage among older persons. Countermeasures to reduce the anticipated death toll among older drivers should address the increased susceptibility to injury of older vehicle occupants in crashes.
Article
Objective. —To assess the relationship between state driver's license renewal policies and fatal crashes involving drivers aged 70 years or older (seniors).Design and Analysis. —Poisson regression methods were used to isolate the relationship between different state policies mandating vision tests, knowledge tests, or road tests for driver's license renewal and fatal crashes involving senior drivers. The analysis controlled for differences among states, other than their renewal policies, likely to influence senior motor vehicle crashes.Setting. —United States, 1985 through 1989.Participants. —All fatal crashes identified in the National Highway Traffic Safety Administration Fatal Accident Reporting System involving at least one driver aged 70 years or older.Main Outcome Measure. —The number of fatal crashes per state in which at least one of the drivers was aged 70 years or older. When a single fatal crash involved more than one senior driver, each was included.Results. —State-mandated tests of visual acuity, adjusted for license renewal period, were associated with lower fatal crash risk for senior drivers (relative risk, 0.93; 95% confidence interval, 0.89 to 0.97). Knowledge tests, when added to vision tests and applied only to seniors, provided a nonsignificant reduction in the senior fatal crash risk (relative risk, 0.91; 95% confidence interval, 0.79 to 1.05).Conclusion. —Tests of vision and knowledge for senior drivers at license renewal merit further attention as a means of improving senior traffic safety.(JAMA. 1995;274:1026-1030)
Article
Policymakers have had a long-standing interest in improving the motor vehicle safety of both younger and older drivers. Although younger and older drivers share the distinction of having more crashes and fatalities per mile driven than other age groups, the problems posed by these two groups stem from different origins and manifest in different ways. A number of state-level policies and regulations may affect the number of motor vehicle crashes and fatalities in these two high-risk groups. A critical review of the existing literature in regard to the risk factors and the effects of various policy measures on motor vehicle crashes in these two high-risk populations provides direction for policymakers and high-priority areas of interest for the research community.
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New findings are presented on the effectiveness (in terms of fatal crash reductions) of state-level public policies related to drunk driving. Conventional estimates of policy effects might be biased because of the endogeneity of policies&semi; this concern is addressed by analyzing the time pattern of policy effects with respect to the date of adoption. For the 0.08 BAC law, the results suggest that a bias upward exists, but the policy is still somewhat effective. Graduated licensing programs for young drivers and the Mothers Against Drunk Driving (MADD) organization are also evaluated for the first time in this type of analysis. The estimated time pattern of effects for graduated licensing suggest that its effects are also overstated in conventional analyses, but the policy is still effective for young drivers. The estimates for MADD do not imply an effect, but this result could be due to the crudeness of the variable used. © 2003 by the Association for Public Policy Analysis and Management.
Article
This paper presents a parameter covariance matrix estimator which is consistent even when the disturbances of a linear regression model are heteroskedastic. This estimator does not depend on a formal model of the structure of the heteroskedasticity. By comparing the elements of the new estimator to those of the usual covariance estimator, one obtains a direct test for heteroskedasticity, since in the absence of heteroskedasticity, the two estimators will be approximately equal, but will generally diverge otherwise. The test has an appealing least squares interpretation.
Article
In late 1989, Illinois revised the length of license term and renewal requirements for older drivers. The term was shortened from 4 to 2 years for those ages 81-86 and 1 year for those ages 87 and up. A mandatory road test which had been required at renewal for all drivers ages 69 and over, was eliminated for those ages 69 to 74. Data are available to explore the impact of these changes on crashes, fatal crashes, crash rates, and licensure rates of senior drivers. Comparisons are made between 1987-1989 averages and 1995 for three age groups: 70-74, 75-80 (the control group that had no changes in requirements), and 81 and up. It does not appear that eliminating the road test for those ages 69 to 74 had any negative impact. On the contrary, it does not appear that the more frequent renewal period for those ages 81 and up produced any benefit compared to the control group. As the number of older drivers continue to increase into the future, the analysis of licensing requirements and their impact is important.