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Rhetorical Analysis Blog
For this blog entry, select a scholarly article from the Hunt Library on a subject that
interests you.
Write a blog in which you:
Identify the elements of the rhetorical situation
▪ Topic – the subject
▪ Writer and role – the creator(s) of the article and attitude toward topic
▪ Audience – the readers (both primary and secondary audience).
▪ Purpose – the reason for writing (informative or persuasive)
Select 3-4 rhetorical strategies from the text
▪ Form (organization and format)
▪ Style (sentence design, word choice, and use if figurative language)
▪ Types of evidence/support (facts, quotes, statistics, case studies, etc.)
▪ Appeal to logos (logic)
▪ Appeal to ethos (credibility)
▪ Appeal to pathos (emotions)
Analyze those strategies
▪ Identify the strategy
▪ Give an example from the text
Evaluate the effectiveness of these strategies
▪ Explain why the strategy successfully appeals to the audience (or why it does
▪ Explain how the strategy accomplishes (or does not) the author’s purpose.
General Format of the Rhetorical Analysis Essay
▪ The introduction should include the title and author of the text to be analyzed,
along with a link to the article, some background on the topic and your thesis
▪ The thesis statement should be a claim about the overall effectiveness of the
▪ The body paragraphs describe the text’s rhetorical situation and then describe
and analyze several of the rhetorical strategies.
▪ The brief conclusion should summarize points about the text’s overall
effectiveness and explore possible future implications.
ENGL 123 September 2017
Car safety seats for children: rear facing for best protection
B Henary, C P Sherwood, J R Crandall, R W Kent, F E Vaca, K B Arbogast, M J Bull
Injury Prevention 2007;13:398–402. doi: 10.1136/ip.2006.015115
See end of article for
authors’ affiliations
Correspondence to:
J R Crandall, University of
Virginia, Center for Applied
Biomechanics, 1011 Linden
Avenue, Charlottesville, VA
22902, USA; jrc2h@
Accepted 28 August 2007
Objective: To compare the injury risk between rear-facing (RFCS) and forward-facing (FFCS) car seats for
children less than 2 years of age in the USA.
Methods: Data were extracted from a US National Highway Traffic Safety Administration vehicle crash
database for the years 1988–2003. Children 0–23 months of age restrained in an RFCS or FFCS when riding
in passenger cars, sport utility vehicles, or light trucks were included in the study. Logistic regression models
and restraint effectiveness calculations were used to compare the risk of injury between children restrained in
RFCSs and FFCSs.
Results: Children in FFCSs were significantly more likely to be seriously injured than children restrained in
RFCSs in all crash types (OR = 1.76, 95% CI 1.40 to 2.20). When considering frontal crashes alone, children
in FFCSs were more likely to be seriously injured (OR = 1.23), although this finding was not statistically
significant (95% CI 0.95 to 1.59). In side crashes, however, children in FFCSs were much more likely to be
injured (OR = 5.53, 95% CI 3.74 to 8.18). When 1 year olds were analyzed separately, these children were
also more likely to be seriously injured when restrained in FFCSs (OR = 5.32, 95% CI 3.43 to 8.24).
Effectiveness estimates for RFCSs (93%) were found to be 15% higher than those for FFCSs (78%).
Conclusions: RFCSs are more effective than FFCSs in protecting restrained children aged 0–23 months. The
same findings apply when 1 year olds are analyzed separately. Use of an RFCS, in accordance with restraint
recommendations for child size and weight, is an excellent choice for optimum protection up to a child’s
second birthday.
n the USA, the rate of vehicle occupant deaths for children 1–
3 years old has decreased by over 50% in the last 30 years1
largely due to increased use of child restraint systems.
Despite these impressive declines, however, motor vehicle
crashes remain the leading cause of death for children 1–4
years of age.2
Although current child restraint systems have been shown to
be effective, further reductions in child passenger injuries may
be achieved by improving car seat features and designs. In
particular, the orientation of car seats (rear facing or forward
facing) probably plays a significant role in car seat effectiveness. By supporting the entire posterior torso, neck, head, and
pelvis, a rear-facing car seat (RFCS) distributes crash forces
over the entire body rather than focusing them only at belt
contact points. In contrast with a forward-facing car seat
(FFCS), an RFCS supports the child’s head, preventing the
relatively large head from loading the proportionately smaller
neck with relatively weak neck musculature.3 The primary
question regarding car seat orientation is at what age children
should make the transition to an FFCS, given that both
biomechanical and practical considerations have to be taken
into account.
In the USA, the American Academy of Pediatrics and the
National Highway Traffic Safety Administration (NHTSA) have
developed guidelines stating that a child should be at least 1
year of age and weigh at least 20 pounds before transitioning
from an RFCS to an FFCS.4 5 The age of the child, in particular,
is an important factor which correlates with the material
properties of the child’s anatomy, such as muscular development and ossification of the cervical spine. Although the policy
of the American Academy of Pediatrics states ‘‘for optimal
protection, the child should remain rear facing until reaching
the maximum weight for the car safety seat, as long as the top
of the head is below the top of the seat back’’, a common
interpretation of these guidelines by parents and caregivers has
been that children should be automatically switched to an
FFCS when they are 1 year old or 9.2 kg (20 pounds). For this
reason, few children in the USA remain rear facing past their
first year of age, despite the fact that there are currently many
RFCSs that have maximum weight limits beyond 9.2 kg. In fact
it has been reported that more than 30% of children are turned
forward facing before they reach 1 year of age.6
In Sweden, children remain in RFCSs up to the age of 4 and
transition directly from the RFCS to a booster seat. Swedish
researchers have used data from a Volvo crash study to compare
the effectiveness of these restraints,7 8 although the lack of
widespread FFCS usage only allows comparison between
RFCSs and forward-facing booster seats. Their most recent
study found that RFCSs had an effectiveness of 90%, relative to
unrestrained children, and the authors supported the policy of
children remaining in an RFCS up to the age of 4 years.
The objective of this paper is to quantitatively compare the
ability of RFCSs and FFCSs to protect child occupants aged
0–23 months, with a particular focus on those 12–23 months of
age, when involved in motor vehicle crashes, using US data.
The National Automotive Sampling System Crashworthiness
Data System (NASS-CDS) is a nationwide motor-vehicle crash
data collection program operated by the NHTSA. This ongoing
survey provides a representative database of fatal and non-fatal
motor vehicle crashes in the USA. The NASS-CDS design,
sampling, and weighting process permits crash estimates to be
extrapolated to provide national estimates.9
As few children in the USA use an RFCS past their second
birthday, child passengers under the age of 2 years were
selected from the NASS-CDS for calendar years 1988–2003. For
Abbreviations: FFCS, forward-facing car seat; ISS, Injury Severity Score;
NASS-CDS, National Automotive Sampling System Crashworthiness Data
System; NHTSA, National Highway Traffic Safety Administration; RFCS,
rear-facing car seat
Car safety seats
the remainder of this paper, children before their first birthday
(0–11 months) will be referred to as ‘‘infants’’ and children
between 1 year of age and their second birthday (12–
23 months) will be referred to as ‘‘1 year olds’’. Children riding
in front or rear seats of passenger cars, sport utility vehicles,
light trucks, and vans were included in the study. Children
exposed to deployed airbags, vehicle fires, or involved in
rollover crashes were excluded. Car seat orientation, seating
position, crash direction, crash severity, injury severity, and
mortality outcome were extracted from the database. As the
database contains limited information on the misuse of car
seats, cases were only excluded when the car seat orientation
was not in accordance with the manufacturer’s specified
orientation. To generate risk estimates at the national level,
the CDS sampling weight variable ratio inflation factor
(‘‘RATWGT’’) was applied to the unweighted data.
Vehicles were classified according to their body type as
passenger cars or light truck vehicles (sport utility vehicles,
light trucks, and vans). Vehicle mass was used as a surrogate
for vehicle size within these two classifications. The change in
velocity during a crash, DV, was used as a proxy for crash
severity. The principal direction of force was used to determine
crash direction and was categorized as frontal (11 to 1 o’clock),
right side (2 to 4 o’clock), left side (8 to 10 o’clock), and rear (5
to 7 o’clock).
As vehicle interior intrusion may play a role in the severity of
occupant injuries, an additional variable was generated to
capture the child seating position relative to the direction of the
crash and its proximity to the location of the car seat. This
variable, called ‘‘proximity’’, was used as a covariate in the
logistic regression models. The variable was coded ‘‘1’’ if the
child was sitting in a position closest to the plane of intrusion,
and ‘‘0’’ if the child was seated in any other position.
The data were analyzed in several steps. Firstly, a descriptive
analysis was performed to describe the characteristics of the
sample population, using both unweighted and weighted data.
Group mean differences for continuous variables were tested
against the t distribution, and differences between group
proportions were tested against the x2 distribution.
Next, a multiple logistic regression analysis was performed
using the weighted data with the Injury Severity Score (ISS)
>9 as the outcome measure.10 An ISS value of 9 or greater is
considered to represent moderate and severe injuries.11 Results
of these analyses are presented as adjusted odds ratios (ORs),
and 95% CIs of the risk estimates were generated from the
adjusted models. p(0.05 was considered significant.
Thirdly, car seat effectiveness (e) was calculated using the
probabilities from the multiple logistic regression models.
Effectiveness (e = 1006((IU2I)/IU), where IU = rate of
severely injured unrestrained children, and I = rate of severely
injured children in car seat) within a population of child
occupants is an estimate of the percentage reduction in the rate
of an injury of specified severity if all children changed from
being unrestrained to being users of the car seat type of
interest.12 Thus, the effectiveness of each type of car seat was
Table 1 Car safety seat orientation by child age
(unweighted data)
1 year olds
292 (70.2)
60 (13.2)
352 (40.5)
124 (29.8)
394 (86.8)
518 (59.5)
416 (100.0)
454 (100.0)
870 (100.0)
FFCS, front-facing car seat; RFCS, rear-facing car seat.
Values are number (%). Infants were aged 0–11 months, and 1 year olds
were aged 12–23 months.
calculated relative to the reference group defined as unrestrained children.
Logistic regression models were adjusted for several confounders to calculate the logit estimates that were eventually
used to calculate the ORs and their significance. These
confounders included child age, vehicle body type, vehicle
weight, DV, seating position, seating location, proximity, and
the direction of the crash (unless direction was specified in the
model, eg, frontal, side, etc). A variable was considered to be a
confounder if it significantly changed the coefficient of the
principal covariate after being added to the model, and if it
improved the fitness of the model.
The multiple logistic regression models were developed for
children in frontal, side, and all crashes. In all models, the OR
represents the relative risk of ISS 9+ injury in those children
restrained in an FFCS compared with those restrained in an
RFCS. The logit estimates and the probabilities (adjusted to
potential confounders) were used to calculate the effectiveness
of the restraint systems relative to the unrestrained children.
When the probability (or effectiveness) as a function of car
seat type was calculated, it was necessary to assign a value to
each of the rest of the independent variables. Vehicle weight
was assigned its median value (1240 kg), and the value of DV
was prescribed as 48 km/h. The vehicle type was set to
passenger cars, the seating position was set to second seat
row, and the child location was set to middle seat. The
probability and effectiveness estimates were calculated as
functions of restraint type and child age for all crash directions
combined (the variable crash direction was not included in the
adjusted effectiveness models).
A total of 1840 children met the age and crash criteria. After
removal of children who were unrestrained (21%) or had
significant restraint misuse (8%) and cases with unknown
restraint use/type (23%), 870 children under the age of 2 were
used in the study (352 RFCS, 518 FFCS). After application of
the NASS weighting factors to reflect national estimates, the
cases represented 191 068 children in RFCSs and 272 153
children in FFCSs. Table 1 shows the distribution of car seat
orientation by child age. As expected, the RFCS group were
significantly younger than the FFCS group.
Table 2 gives a description of the child, crash, and vehicle
characteristics using the weighted data. The weighted data
trends were similar to those of the unweighted data, with the
primary differences between groups being child age, weight,
and height. The significant differences between other variables
were primarily due to the large sample size, rather than
substantial differences between the groups.
Table 3 gives OR (95% CI) derived from the adjusted logistic
regression models using the weighted data. The models were
adjusted for child age, vehicle body type, vehicle weight, DV,
seating position, seating location, and direction of crash.
Compared with the RFCS group, the children in the FFCS
group were more likely to sustain ISS 9+ injuries in side crashes
(OR = 5.53, 95% CI 3.74 to 8.18), and in all crashes (OR = 1.76,
95% CI 1.40 to 2.20). The benefit of rear facing had borderline
significance when considering frontal crashes alone (OR = 1.23,
95% CI 0.95 to 1.59). When the previous analysis was repeated
for infants and 1 year olds separately, the use of an RFCS was
beneficial for infants in side crashes and all crashes, and for 1
year olds in frontal crashes and all crashes, with ORs ranging
from 1.79 to 6.16. Estimates for other age and crash direction
combinations were unable to be calculated because of small
sample sizes.
Table 4 shows the effectiveness of each type of car seat in
preventing injuries of moderate to great severity, calculated
Henary, Sherwood, Crandall, et al
Table 2 Child, vehicle, and crash characteristics (weighted data)
Age (months)
Weight (kg)
Height (cm)
Vehicle type
Passenger car
Light truck
Vehicle weight (kg)
Crash direction
Right side
Left side
Child row
DV (km/h)
MAIS score
MAIS (injured & uninjured)
Frontal crashes
Side crashes
All crashes
(n = 191 068)
(n = 272 153)
(N = 463 221)
151 510 (83.0%)
32558 (17.0%)
63184 (23.2%)
208 969 (76.8%)
87 812 (46.0%)
97 831 (51.2%)
5425 (2.8%)
7.6 (2.3)
62.7 (9.9)
t test/ Pearson x2
p Value
22 1694 (47.9%)
24 1527 (52.1%)
x2(1) = 255650
125 005 (45.9%)
139 577 (51.3%)
7571 (2.8%)
12.0 (3.7)
72.7 (11.3)
212 817 (45.9%)
237 408 (51.3%)
12 996 (2.8%)
10.1 (3.9)
67.2 (16.9)
x2(2) = 1.49
t = 2580
t = 2365
147 758 (77.3%)
14 559 (7.6%)
12 046 (6.3%)
16 705 (8.7%)
1369 (304.1)
215 932 (79.3%)
11 110 (4.1%)
35 072 (12.9%)
10 039 (3.7%)
1328 (343.2)
363 690 (78.5%)
25 669 (5.5%)
47 118 (10.2%)
26 744 (5.8%)
1344 (343.3)
x2(3) = 19050
t = 42.2
152 967 (56.2%)
29 208 (10.7%)
11 701 (4.3%)
29 422 (10.8%)
48 855 (18.0%)
241 389 (52.1%)
42 780 (9.2%)
30 710 (6.6%)
46 540 (10.1%)
101 802 (22.0%)
x2(3) = 6791
53 875 (19.8%)
202 802 (74.6%)
15 476 (5.7%)
0 (0.0%)
19.8 (10.2)
107 388 (23.2%)
339 707 (73.3%)
16 115 (3.5%)
11 (0.0%)
18.7 (12.8)
x2(1) = 12944
t = 272.8
53 513 (28.1%)
136 905 (71.7%)
639 (0.3%)
11 (0.0%)
17.0 (9.4)
171 706 (89.9%)
18 297 (9.6%)
570 (0.3%)
54 (0.03%)
74 (0.04%)
312 (0.16%)
0 (0.0%)
55 (0.03%)
230 695 (84.8%)
38 363 (14.1%)
1220 (0.5%)
625 (0.2%)
520 (0.19%)
50 (0.02%)
42 (0.02%)
638 (0.23%)
402 401 (86.9%)
56 660 (12.2%)
1790 (0.4%)
679 (0.2%)
594 (0.13%)
362 (0.08%)
42 (0.01%)
693 (0.15%)
x (7) = 3400
0.20 (0.5)
0.09 (0.3)
0.11 (0.4)
0.20 (0.4)
0.26 (0.5)
0.17 (0.4)
0.20 (0.5)
0.18 (0.5)
0.14 (0.4)
t = 0.6
t = 254.5
t = 243.7
FFCS, front-facing car seat; MAIS, Maximum Abbreviated Injury Score; RFCS, rear-facing car seat; SUV, sports utility vehicle.
Values are number (%) or mean (SD).
with respect to unrestrained children, based on the adjusted
logistic regression models. RFCSs had higher effectiveness
values than FFCSs for each age group (infants, 1 year olds, all).
The estimates were age sensitive, as they were higher for
infants than for 1 year olds.
Regardless of the age group considered, RFCS use resulted in
lower risk of injury than FFCS use for crashes of all directions.
The unexpected finding from these results is the higher benefit
for children in RFCSs compared with FFCSs in side impact
crashes. The biomechanical benefits of RFCSs are primarily
apparent in frontal impacts. In fact, in a purely lateral crash, the
only significant differences between RFCSs and FFCSs are the
geometry of the side wings and the location at which the
restraint attaches to the vehicle. Most side crashes, however,
are not purely lateral and probably have a forward component.13 14 When a child is in an RFCS, a frontal crash component
results in the head moving farther into the car seat ‘‘cocoon’’
with the likelihood of additional protection of the side wings.
When in an FFCS, a frontal crash component causes the child’s
head to move forward and further away from the car seat,
limiting or removing any benefit of the side wings. Further
research is necessary to determine if this factor is responsible
for the significant benefit of RFCSs in side crashes, or if other
factors are also important.
It is also notable that RFCSs had higher effectiveness values
than FFCSs for each age group considered (infants, 1 year olds,
Table 3 Adjusted odds ratios of Injury Severity Score (ISS) 9+ comparing forward-facing with
rear-facing car seats
Adjusted models
Frontal crashes
Side crashes
(right and left)
All crashes
(including rear)
Without proximity term
With proximity term
Infants only
1 year olds only
(0.95 to 1.59)
(0.95 to 1.59)
(N/A) …
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