Vol.3, No.11, 689-697 (2011)
opyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
Preventable head and facial injuries by providing free
bicycle helmets and education to preschool children
in a head start program
Thein Hlaing Zhu1*, Mary O. Aaland1, Connie Kerrigan2, Renee Schiebel2, Heather Henry2,
Lisa Hollister1
1Parkview Hospital Adult and Pediatric Level II Trauma Center, Fort Wayne, USA;
*Corresponding Author: thein.hlaing@parkview.com, thein.zhu@gmail.com
2Parkview Community Nursing Program, Parkview Community Health Improvement Program, Fort Wayne, USA.
Received 26 August 2011; revised 12 October 2011; accepted 27 October 2011.
The objectives of the study were to determine
helmet use rates, incidence rates (IRs) of head
and facial injuries for population attributable
fraction (PAF) estimation, and to elucidate the
magnitude of and changes in PAFs as the result
of helmet use changes among preschool chil-
dren. A study consisting of cross-sectional (sur-
vey) and longitudinal (follow-up) component
was designed by including a randomly selected
group of participants (n = 322) from 10 Head
Start sites provided with free bicycle helmets
along with a s ubgr ou p of pr ior hel met owners (n
= 68) from the other random group (n = 285). All
participants received bicycle helmet education.
Helmet use surveys were conducted in May (1st
Survey) and November 2008 (2nd Survey). The
helmet owners were followed up to determine
IRs, and incidence rate ratios (IRRs) for head
and facial injuries. PAFs were computed using
IRs as well as helmet use rates and IRRs. Hel-
met use rates increased significantly from the
1st to the 2nd Survey. The mean follow-up per-
son-time was 5 months. The IRs for head, face
(all portions), and face (upper/mid portions) in-
juries were higher in non-helmeted than hel-
meted riders. By using IRs, PAFs for the 3 inju-
ries among the riders in both groups of helmet
owners were 77%, 22%, and 32% respectively.
The PAFs for each of the above injuries de-
creased by about 10% as helmet use rates in-
creased. The magnitude of and changes in
preventable head and facial injuries following
free bicycle helmet distribution and education
among helmeted riders was elucidated in this
Head Start preschool children population.
Keywords: Head Injury; Facial Injury; Free Helmet
Distribution; Head Start; Preschool Chil dren; PAF
Head Start Programs exist in every state in the United
States, and 908,412 children were enrolled in 2007 na-
tionwide; of these, about 90% were preschool age [1].
Head Start is a federally funded preschool program that
provides health, education and social services to children
from low-income families that are at or below the fed-
eral poverty level. The Community Action of Northeast
Indiana (CANI) Head Start Program in Fort Wayne,
Indiana serves over 800 preschool children.
The trauma program of the Parkview Hospital Level II
Trauma Center in Fort Wayne, Indiana planned to dis-
tribute 800 free helmets to preschool children ages 3-5
years at the CANI Head Start sites in 2007-2008 to en-
courage helmet use both at school and home. Of these,
about 400 helmets were available for the first year bicy-
cle season and the remaining 400 for the next year sea-
son. One research question that intrigued the research
personnel before implementing the program was, “to
what extent could head and facial injuries be prevented
if this population is provided free bicycle helmets and
education?” In other words, could we measure the popu-
lation attributable fractions for head and facial injuries
among helmeted riders?
In reviewing the literature, the methodology for esti-
mation of population attributable fraction (PAF) of bicy-
cle related head injuries could be calculated by two for-
mulas: one calculation using the incidence rates of inju-
ries and the other calculation based on bicycle helmet
use rate and helmet effectiveness [2]; the same author
demonstrated that PAF decreased as helmet use rate in-
creased by simulation model. Again, bicycle helmet ef-
T. H. Zhu et al. / Health 3 (2011) 689-697
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
fectiveness against head and facial injuries by case-con-
trol studies were shown for all ages [3,4] and for < 6
years old children [5]. Previous studies on population-
based head injury rates among children 5 years old and
under were based on hospital records [6,7]. Studies based
on all cases (hospital as well as non-hospital cases) aris-
ing from the community to estimate either head and/or
facial injury incidences are rare. The present study ob-
jectives were 1) to determine helmet use rates, incidence
rates of head and facial injuries among helmeted and
non-helmeted riders in the preschool population for PAF
estimation; 2) to elucidate the magnitude of and changes
in PAFs as the result of helmet use changes in the same
2.1. Study Setting
A pilot sample survey of 221 families at 6 CANI Head
Start sites in September 2007 showed that 90% of 3-5
year old children owned a bicycle or wheeled riding toy
and 20% of them possessed a helmet. Ten of 11 sites that
portray a diverse population with multiple languages and
ethnicities in Allen, Noble and Whitley counties were
selected and the one with predominant majority of white
children (n = 34) was excluded. All sites provide morn-
ing (AM) and afternoon (PM) classes except one site,
which offers only AM classes.
2.2. Study Design
It has been stated that randomized controlled trials are
neither feasible nor ethical for study of bicycle helmet
effectiveness against head injury and that cohort studies
are also unfeasible due to low incidence of the event [8].
To achieve our objectives, we devised a study design
consisting of cross-section (survey) and longitudinal
(follow-up) component in helmet owners as follows:
First, the principal investigator and a team member se-
lected two groups by a toss of a coin so that each group
consisted of either the AM or PM classes from each of
the 8 sites. From the remaining two sites, the site with
only AM classes (10th site) was combined with the other
site (9th site) that had fewer children in its PM classes to
form into a subgroup that had comparable number of
children with those in AM classes of the 9th site, and
then these two subgroups were again selected by a toss
of a coin to join the above two groups. Second, one of
the two groups was randomly selected to be provided
with 400 free bicycle helmets and helmet education (HE).
This group formed the main focus of our study. The
other group was provided with bicycle helmet education
only (E) (and all would receive the remaining 400 free
helmets in 2009 bicycle season). As some participants of
the E group could own bicycle helmets (expected from
the pilot study), we also took this subsample into our
study to increase the sample size and it was termed as
H’E group where H’ represented those participants who
owned a helmet at the beginning of the study (prior hel-
met owners). We employed the HE and H’E groups to
conduct surveys for estimation of helmet use rates at the
beginning and end of study, and for follow-up study for
estimation of IRs, incidence rate ratios (IRRs). PAFs
were ultimately computed. Wearing a helmet was con-
sidered as exposure and without wearing a helmet was
non-exposure while riding a bicycle or wheeled riding
toy. The person-time determination for estimation of IRs
among helmeted and non-helmeted riders is described in
section 2.6.
2.3. Participants, Provision of Helmets and
The eligibility criteria for a case were: a child 3 - 5
years old and his/her siblings in the same age range, reg-
istered with the CANI Head Start Program, possession
of a bicycle or a wheeled riding toy, and the child’s
caregiver speaking English or Spanish. The study started
to recruit participants’ caregivers in mid-May 2008 by a
team of 7 Parkview Hospital community nurses and 6
Spanish speaking CANI personnel. The study ended on
November 15, 2008.
The provision of free helmets was done by the nurses
to the HE group in area site classrooms. The helmets
were manufactured by Bell Sports Inc, Rantoul, IL, USA
and comply with the Consumer Product Safety Commis-
sion bicycle safety standards. If a caregiver from the E
group expressed a concern about obtaining a helmet be-
fore the end of the study, a voucher was issued to receive
a free helmet and fitting from the hospital’s safety store.
Two professional health educators provided the class-
room education to both caregivers and children from
both groups through a video (which had already been
used regularly for 9 years in area schools) on rules of
bicycling and the importance of proper helmet use to
prevent head injury, as well as a classroom melon drop
demonstration with and without a helmet at the time of
recruitment. Besides the video, the caregivers received
information pamphlets on the risks of head injury from a
bicycle crash, the effectiveness of helmets’, strategy’s to
fit helmets, and encouraging their use while children are
still young. Spanish language was used in translation for
questionnaires, and other forms, and for communication
with the Hispanic caregivers. Each family that submitted
completed questionnaires was presented with a retail gift
card. One family was awarded a grand prize of a large
TV by random drawing. Approval from the Parkview
T. H. Zhu et al. / Health 3 (2011) 689-697
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
Health Institutional Review Board to undertake this
study was obtained in April 2008.
2.4. Definitions
Helmet use was defined as a child wearing a helmet
“always” or “most of the time” while riding, and non-
use was defined as when the child “did not wear” or
wore a helmet “some of the time” while riding the ve-
hicle [9].
The definitions for head and facial injuries followed
closely to those of Thompson et al. [10] and were
phrased understandable to the caregivers. A head injury
was defined as consisting of superficial cuts/scrapes
(lacerations/abrasions), bruises on the scalp, bumps to
the head and passing out (possible concussion) and bro-
ken bones in the head (skull fractures). A facial injury
for all areas consisted of superficial cuts/scrapes, and
bruises to the face, including the forehead, eye (external),
nose, mouth (intra-oral), cheek, ear (external), chin (lower
jaw), and facial bone fractures. The upper and mid-por-
tion of face was taken as occurring to the forehead, eye,
nose, cheek or ear.
2.5. Data Sources and Measurement
2.5.1. Helmet Use Study Component
The nurses provided a simple, self-administered, pre-
tested, and structured questionnaire to the caregivers to
record helmet use in HE and E groups at the beginning
(1st Survey) and end of study (2nd Survey). H’E was
identified after the 1st Survey. The questionnaire con-
tained data on the caregivers including highest education
attained, ethnicity, and language spoken. The data gath-
ered on the children included sex, type of vehicle pos-
sessed, helmet ownership, and the numbers of helmet
use while riding the vehicle. To supplement the helmet
use by questionnaire method, the nurse used observation
method by asking the caregiver during the home visit
(see below) to let the child ride the bicycle or other rid-
ing vehicle, and observed whether the child rode and
wore a helmet with or without prompting in the HE
group as was done in one study [11].
2.5.2. Injury Study Component
Another simple, self-administered, pretested, and
structured questionnaire was also given to the caregivers
for recording demographic information of both caregiv-
ers and children, and injuries that occurred during the
follow-up. The variables for each injury included,
among others, the date of injury, helmet wearing status,
nature of injury, anatomic location of injury, and type of
treatment sought. In addition, a systematic random sam-
ple of 20% of families by site from the HE and E groups
were selected to use as a validation subsample of study
subjects to carry out a one-time home visit by the field
team members. It began 4 weeks after the recruitment
for determining any discrepancies on recording injuries
and to verify injury location diagnoses.
All questionnaires were collected at the Head Start
sites, by US mail services, and at home visits. Telephone
calls were periodically made to increase the response
2.6. Statistical Analysis
Helmet uses among helmet owners were analyzed by
HE and H’E groups and Survey. Statistical tests were
performed using 2-tail P value <0.05 as statistical sig-
nificance [12].
A child possessing a helmet could have multiple epi-
sodes of bodily injuries including head and/or face from
falls while riding, switching helmet wearing to non-
wearing and vice versa, during the following-up period.
Based on this context, assignment of person-time (per-
son-days) contributing to an injury including the head
and face within a child was determined as the period of
exposure up to the moment of that injury event while
riding by wearing a helmet or period of non-exposure
without wearing a helmet. In other words, a child could
have a number of exposure and non-exposure person-
days depending upon helmet wearing status at the time
of injury event while riding. Those children without re-
porting any injuries and therefore unable to know their
helmet wearing experience were excluded from the per-
son time determination. Based on these assumptions, the
person-days for incidence rates (IRs) were computed
from the participants’ start and end dates of follow-up
and the dates of injuries as follows:
1) For a child, either with one or more injury events,
wearing or not wearing a helmet at one or all injury
dates, person-days = End Date – Start Date.
2) For a child with 2 or more events, person-days for
the 1st or with the same continuously wearing or not
wearing occurring events = Injury Date (of 1st or that of
last continuous event) – Start Date. For subsequent dif-
fering wearing event (s), person-days = Injury Date (of
that or last event] – Injury Date (of previous event) and
were repeated if such alternate (s) of wearing/non-
wearing continued to occur. But the person-days for the
final injury event = End Date – Last Counted Injury
Date so that the child total person-days were completely
distributed by helmet wearing status.
The sum of helmeted or non-helmeted person-days
was taken as the denominator for respective IR. Inci-
dence rate ratios (IRRs) along with 95% CI values were
calculated and the values of helmet effectiveness [13] in
this preschool age were derived. PAFs for head and fa-
T. H. Zhu et al. / Health 3 (2011) 689-697
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cial injuries were computed as follows [2]:
where PAF = Population Attributable Fraction,
IRt = Incidence rate of injury in all riders,
IRe = Incidence rate of the injury in helmeted riders.
where Pnh = Proportion of riders who do not wear a hel-
RR or IRR = Relative risk of injury among the non-
helmeted riders Compared to helmeted riders.
Validation for head and facial injuries was done in
both HE and E groups as some of the E group partici-
pants, besides the prior helmet owners, acquired helmets
from vouchers and other sources during the study period.
Follow-up loss analysis from each study component was
confined to the HE group (because of small sample size
in H’E group) by comparing the distribution of demo-
graphic characteristics of children and their caregivers
between the completed follow-up category and the loss
in follow-up category.
3.1. Baseline Characteristic Features
The baseline characteristic features of the study par-
ticipants and their caregivers are shown in Ta bl e 1 . The
distribution of demographic variables of participants and
of caregiver’s education and ethnicity between the HE
and H’E was not statistically significant. However, the
distribution of caregiver’s education and ethnicity in the
Helmet Use Study and caregiver’s education in the In-
jury Study between HE and E groups were statistically
significant. Figure 1 shows flow of participants and
study sizes through each stage of the two study compo-
3.2. Vehicle Ownership, Helmet Distribution
and Use
The majority of the children owned a bicycle (over
80%), followed by a scooter (27%), tricycle (25.0%) and
rollerblades/skates (over 15%). This pattern was ob-
served in the HE and E groups. All participants received
free helmets in the HE group irrespective of their prior
ownership. Participants in the E group received 41 free
helmets by vouchers and a few of them obtained helmets
from other sources. A total of 97 helmet owners, includ-
ing prior helmet owners, were reported at the end of
study in this group. Highly increases in helmet use rates
were observed from the 1st to the 2nd Survey in HE and
H’E groups but statistically significant increase in the
former group (Table 2).
3.3. Incidence of Head and Facial Injuries by
Helmet Wearing Status
The mean ± SD follow-up months for the HE group
and H’E group were 4.8 ± 1.4 and 5.2 ± 1.1, respectively.
About 67% of head and facial injuries were related to
bicycle-riding. The IRs for head and facial injuries were
much lower in the helmeted than non-helmeted riders in
HE and in both groups combined (Table 3). As the
number of head and facial injuries in the H’E group were
small, the findings in this group were not shown sepa-
rately and in subsequent tables. The 95% CIs of IRR
values for head and facial injuries (all portions) between
helmeted vs. non-helmeted riders were below 1.0 in HE
group (Table 3).
During home visits, 62 preschool children were
available for the observation. The caregivers agreed to
let 51 children ride in front of the home visiting nurse
and 50 children participated. Of those participated, 34
(68.0%) wore a helmet while riding, with a breakdown
of 21 (42.0%) children remembering to wear a helmet
following a prompt from the caregiver about the helmet,
and 13 (26.0%) wore without the prompt.
3.4. Helmet Effectiveness
Helmet effectiveness was derived from IRRs (Table
3). The bicycle helmet effectiveness value for head in-
jury was 94% for helmet users in the HE group and the
finding was similar in both groups combined. The hel-
met effectiveness was 62% for all facial areas, and that
for the upper and mid-portion of the face was 75% in HE
group, and the values for facial injuries were higher than
those in both groups combined.
3.5. Preventable Fractions
The PAFs as measured by the IRs for the head, face (all
portions) and face (upper/mid portions) in HE group
were 75%, 25% and 37% respectively and the corre-
sponding values for facial injuries were relatively lower
in the combined group (Tabl e 3). The PAF values in HE
group when measured by helmet effectiveness and the
helmet use rate were 84%, 36% and 51% for the above
corresponding injuries at the baseline, and each value
decreased at the end of study as the result of increase in
helmet use rates (Table 4). Again, the corresponding
values for facial injuries were slightly lower in the com-
bined group. However, the overall trend and magnitude
of difference were similar in HE and both groups com-
T. H. Zhu et al. / Health 3 (2011) 689-697
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Table 1. Comparison of baseline characteristic features of two study components.
Helmet Use Study Injury Study
b H’Ec χ2 testd
(HE v. E)
χ2 testd
(HE v. H’E)HEa E
b H’Bc χ2 testd
(HE v. E)
χ2 testd
(HE v. H’E)
Participants, n 322 285 68 254 213 54
Sex, % nse nse nse nse
Male 50.0 55.4 55.9 49.6 55.9 51.9
Female 50.0 44.6 44.1 50.4 44.1 48.1
Age (y), % nse nse nse nse
3 27.0 26.3 17.6 29.1 29.6 22.2
4 38.8 38.6 48.5 36.6 39.0 46.3
5 34.2 35.1 33.8 34.3 31.5 31.5
Caregivers, n 246 215 56 190 159 43
Education, % P < 0.05nse P < 0.05 nse
Some schooling 26.4 24.7 19.6 25.3 21.4 20.9
High school diploma 42.7 28.4 32.1 44.2 28.9 30.2
College education 22.4 28.8 35.7 23.2 31.4 37.2
Other 0.8 0.9) 1.8 1.1 1.3 2.3
Missing 7.7 17.2 10.7 6.3 17.0 9.3
Ethnicity, % P < 0.05nse nse nse
Black 43.5 33.5 30.4 38.4 30.2 23.3
Hispanic 25.6 29.8 23.2 26.8 30.2 23.3
White 28.0 30.7 42.9 32.6 32.1 48.8
Other 2.4 5.6 3.6 2.1 6.9 4.7
Missing 0.4 0.5 0 0 0.6 0
aHE = Provision with free helmet distribution and helmet education; bE = Provision with helmet education only; cH’E = A subgroup of E group with prior hel-
met owners (See explanation for prior helmet owners in text); dStatistical tests were done after excluding other and missing categories; ens = Not significant.
Table 2. Helmet use rate by group and survey.
HE Groupb H’E Groupc Combined
Helmet Wearing Statusa
1st Survey 2nd Survey 1st Survey 2nd Survey 1st Survey 2nd Survey
Yes 65.6 80.5 49.3 62.2 59.0 77.4
No 33.4 19.5 50.7 37.8 41.0 22.6
Total 100.0 (99)d 100.0 (221) 100.0 (67) 100 (45) 100.0 (166) 100.0 (266)
Difference between 1st and
2nd Surveys
z = 2.696
P < 0.01
z = 1.351
P > 0.05
z = 4.076
P < 0.001
aHelmet wearing status not documented: 2 cases in 1st Survey and 7 cases in 2nd Survey under HE group, and 1 case in 1st Survey and 1 case in 2nd Survey under
H’E Group; bHE = As in Table 1; cH’E = As in Table 1; dNumber of participants in parentheses.
T. H. Zhu et al. / Health 3 (2011) 689-697
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Table 3. Incidence rates of head and facial injuries per helmet wearing status in helmet owners.
Helmet Owners (n = 82) in HE Group All Helmet Owners (n = 105)a
Helmet Wearing Status
Head Face
(all portions)
(upper/mid) Head Face
(all portions)
No. 10 20 6 12 26 8
Person Time (days) 12,965 12,965 12,965 16,742 16,742 16,742
Helmeted and
Non-Helmeted Riders
IRb/100 children/year 28.15 56.31 16.89 26.16 56.68 17.44
No. 2 12 3 2 15 4
Person Time (days) 10,361 10,361 10,361 12,360 12,360 12,360
Helmeted Riders
IRb/100 children/year 7.05 42.27 10.57 5.91 44.30 11.81
No. 8 8 3 10 11 4
Person Time (days) 2604 2604 2604 4382 4382 4382 Non-Helmeted Riders
IRb/100 children/year 112.14 112.14 42.05 83.29 91.62 33.32
Helmeted vs.
Non-Helmeted Riders
95% Confidence interval
(0.01 - 0.30)
(0.15 - 0.92)
(0.05 - 1.25)
(0.02 - 0.32)
(0.22 - 1.05)
(0.09 - 1.42)
Helmet Effectiveness
(1-IRRc) 94% 62% 75% 93% 52% 65%
PAFd (%) 75.0 24.9 37.4 77.4 21.8 32.3
aAll helmet owners in HE and prior helmet owners in H’E groups; bIncidence rate; cIncidence rate ratio; dte
PAF , (See explanation for the parameters
in text).
Table 4. Population attributable fraction (PAF%) at baseline and end of study.
Helmet Owners in HE Group All Helmet Ownersa
Relative Riskb Baseline End of StudyDifference
In PAF Relative RiskbBaseline End of Study Difference
Head 0.06 0.07
Helmet Use Ratec (%) 65.6 80.5 59.0 77.4
PAFf (%) 84.4 75.3 9.1 84.5 75.0 9.5
Face (All Portions) 0.38 0.48
Helmet Use Ratec (%) 65.6 80.5 59.0 77.4
PAFf (%) 36.0 24.1 11.9 30.8 19.7 11.1
Face (Upper/Mid) 0.25 0.35
Helmet Use Ratec (%) 65.6 80.5 59.0 77.4
PAFf (%) 50.8 36.9 13.9 43.2 29.6 13.7
aAs in Table 3; bRelative risk (IRR) of corresponding injury among helmeted compared to non-helmeted riders; see Table 2; cTaken from Table 2;
, (See explanation for the parameters in text).
T. H. Zhu et al. / Health 3 (2011) 689-697
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Assessed for Eligibility from
10 Head Start sites
(n = 703)
Excluded (n = 96)
Not meeting inclusion criteria (n=7)
Declined to participate (n=42)
Not completed recruitment paperwork (47)
Study Dataset
(n = 607)
Received free helmet and
education (HE
) (n = 322)
Received education
) (n = 285)
Received helmet education
) (n = 68)
Helmet Use Study Injury Study Helmet Use StudyInjury Study
(n = 101 prior helmet
owners in 1
and 228 of 246
owners in 2
Loss to
(n = 76)
Loss to
(n = 68)
(n = 68 in 1
and 51 prior helmet
owners in 2
Loss to
(n = 17)
Loss to
(n = 14)
(n = 254)
(n = 54)
Random Sampling
Figure 1. Comparing flow of participants and study sizes through each stage of study component. aHE as in Table1; bE as in Table 1;
cH’E as in Table 1; d14 participants that might have lost their helmets and 4 did not give information on helmet ownership.
history of needing medical
rtments or physician offices;
from home visits were correct in 90.5%
e 1).
he source population in the study
bers of helmet owner were small
, showed
3.6. Other Outcomes 4. DISCUSSION
A total of 9 cases gave a
attention at emergency depa
cases did not wear a helmet. All injuries were mainly
due to falling off of the bicycle. No hospitalizations or
deaths were reported from injuries while riding bicycles
or toys.
The reported characteristic features of caregivers for
injury data
Openly accessible at
8/42) of participants in the HE group and 97.6% (40/
41) in the E group. In both groups combined, the posi-
tive and negative predictive values for head injury were
100% (7/7) and (45/45) and the facial injuries (all areas)
were 85% (11/13), and 96% (43/45), respectively.
Approximately 20% to 25% in HE or H’E group by
study components were lost to follow-up (Figur
owever, the distributions of demographic characteris-
tics of children and parent information were not signifi-
cantly different between the completed follow-up vs. the
loss in follow-up categories in both the component stud-
ies under the HE group. The differences in distributions
in H’E group were not analyzed due to small numbers of
loss to follow-up.
The similarity in distributions of demographic vari-
ables of preschool children participants in the HE and E
groups may represent t
area. Although the num
H’E group, it may be a complement to the whole
study by examining the results in HE, and HE and H’E
combined (Ta bles 2-4). The increase in helmet use from
the 1st to the 2nd Survey in the HE and H’E groups among
the preschool children might be due to provision of multi-
faceted bicycle helmet education to the caregivers and
their children, and inclusion of reinforcing factors, such as,
use of Spanish language for Spanish speakers and provi-
sion of incentives [14]. Many helmet wearing occurrences
in children could be due to parental prompting.
There were a few studies on IR for head injury in pre-
school age children. One study, taking injured patients
resulting from bicycle crashes from one source and
population denominator from another source
at IR among 0 - 4 years old in Washington State for
head injury was 0.068 per 100 population in a year [7]
The rate was much lower when compared to our corre-
sponding rate, as the former study was based on emer-
T. H. Zhu et al. / Health 3 (2011) 689-697
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
of multiple episodes
rs (Ta bl e 3 ). These findings indicate the sig-
our local Head
ta were available
254) of participants in the HE
monstrated the public health importance and our
program’s worth by elucidating the magnitude of pre-
juries in helmeted riders fol-
grateful for the funding support for this research study from
the Physicians’ Council of the American Trauma Society. Additional
arkview Hospital and
Parkview Community Health Improvement Program. We thank Mary
Start program fact sheet. U.S. Department of Health and
ashington DC.
) Population preventable fraction of
gency department data only.
This might be the first innovative longitudinal (fol-
low-up) study in helmet owners to estimate IRs based on
person-days and helmet protective effects for head and
facial injuries. We took advantage
injuries occurring within a child (54/105), including
those treated at home and outpatient clinics. A similar
finding of helmet protective effects between this and
other studies, for instance, helmet protective effect of
85% for head [15], and of 65% for upper and mid-face
injuries [10], signifies the appropriateness of our study
The rates of injuries were much higher in non-hel-
meted children. For instance, the rate for head injury was
14 times (83.29/5.91) higher in non-helmeted than hel-
meted ride
ficance of reduction of head and facial injuries by
helmet wearing while riding and starting at the preschool
age. A similar study of increase in helmet use and de-
crease in incidence of bicycle-related head injury was
shown in 5-14 year-old children [16].
Perhaps, this is also the first study to determine PAF
as an indication of public health importance and demon-
stration of our program’s worth [17] by providing free
bicycle helmets and helmet education in
art Program. For instance, of 100 vehicle-related head
injuries occurring in this target preschool population, 77
of them would be avoided if every educated rider in the
population had worn a helmet; see Table 3. We found
the PAFs decreased as the helmet use rates increased as
shown in simulation by Kopjar [2]. In this study, PAFs
estimated by IRs seem to represent the average values
when compared with those values based on helmet use
rate and helmet effectiveness. The similarity of findings
on helmet use rates by observation and reporting, the
high predictive values for head and facial injuries on
validation, and the similarity of demographic data of
caregivers and their children between completed and
follow-up loss denote the study data were reasonably
reliable. Rockhill et al. mentioned the misuse of PAF
with respective to computational and interpretational
issues [18]. We employed the PAF formulas that were
suitably created for bicycle related injuries [2]. Kopjar
commented that the protective effect of helmets was not
confounded by previous non-use, and there was no evi-
dence of competing risks replacing the ones removed by
helmet use; these conditions were the basic criteria for
external validity of PAF estimates [2].
The injury events in the follow-up study were based
mainly on reporting. Person-time da
only from 32.3% (82/
oup and 42.6% (23/54) in the H’E group. Verification
of types of helmet used was not done at the time of in-
jury. Few off-road head and facial injuries were reported
from riding bicycles and other wheeled-riding toys
within the observation period. Among those children
reported without injuries, 45 children in the HE group
and 13 children in the H’E group used bicycles with
training wheels. Due to low incidence of head and facial
injuries, PAFs by ethic groups could not be determined.
In addition, we were unable to collect and assess the
injury data by home visit for the entire follow-up period.
The extent of follow-up loss of participants, the possible
reporting biases, and the findings were mentioned in the
We de
ventable head and facial in
lowing the free bicycle helmet distribution and helmet
education in this Head Start preschool children popula-
We are
financial requirements were supplemented by P
ee Freeze, the Director of the CANI Head Start Program in Fort
Wayne for allowing the study to take place at 10 sites. Last, but not
least, we appreciate the Parkview Hospital Community Nursing per-
sonnel and the CANI staff for their assistance in the field work.
[1] Administration for Children and Families (2008)
Human Services, W
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