1. family and parenting
2. children

Effects of Interventions to
INCREASE USE OF BOOSTER SEATS IN
MOTOR VEHICLES FOR 4-8 YEAR OLDS
Prepared by
John Ehiri, PhD, Associate Professor
Department of Maternal and Child Health
School of Public Health
University of Alabama at Birmingham
Birmingham, AL 35294-0022
William King, DrPH, Professor
Department of Pediatrics
University of Alabama at Birmingham
Henry O.D. Ejere, MD
Department of Medicine
Metropolitan Hospital, New York City
Peggy Mouzon, AB, AMLS
Mouzon Information Services, Michigan
Prepared for
AAA Foundation for Traffic Safety
607 14th Street, NW, Suite 201
Washington, DC 20005
Tel: 202 -638-5944
Fax: 202 -638-5943
www.aaafoundation.org
February 2006
Contents
Acknowledgments / 5
References / 55
Executive Summary / 6
Appendices / 65
Introduction / 9
Appendix 1: Search strategy
Design and methods / 14
Appendix 2: Characteristics of
Criteria for considering studies
for this review (protocols) . . . . . . . . . . . . .15
Search strategy for identification
of studies . . . . . . . . . . . . . . . . . . . . . . . . . .17
Description of studies . . . . . . . . . . . . . . . . . . .25
Effects of Education Versus
Methodological quality of
No Intervention
Education versus no intervention. . . . . . . . . .37
If trade or manufacturer’s names are mentioned, it is only because they are considered essential to the object of
this report and their mention should not be construed as an endorsement. The AAA Foundation for Traffic Safety
does not endorse products or manufacturers.
2006, AAA Foundation for Traffic Safety
©
2
list of figures & tables
Figure 1.
Results / 37
This publication is distributed by the AAA Foundation for Traffic Safety at no charge, as a public service. It may not
be resold or used for commercial purposes without the explicit permission of the Foundation. It may, however, be
copied in whole or in part and distributed for free via any medium, provided the AAA Foundation is given appropriate credit as the source of the material. The opinions, findings, and conclusions expressed in this publication are
those of the authors and are not necessarily those of the AAA Foundation for Traffic Safety or of any individual
who peer-reviewed this report. The AAA Foundation for Traffic Safety assumes no liability for the use or misuse
of any information, opinions, findings, or conclusions contained in this report.
ongoing studies . . . . . . . . . . . . . . . . . . . . .69
Method of the review . . . . . . . . . . . . . . . . . . .19
included studies. . . . . . . . . . . . . . . . . . . . .32
This report was funded by the AAA Foundation for Traffic Safety in Washington, D.C. Founded in 1947, the AAA
Foundation is a not-for-profit, publicly supported charitable research and education organization dedicated to
saving lives by preventing traffic crashes and reducing injuries when crashes occur. Funding for this report was
provided by voluntary contributions from the American Automobile Association and its affiliated motor clubs, from
individual members, from AAA-affiliated insurance companies, as well as from other organizations or sources.
for identification of studies. . . . . . . . . . . . .65
Distribution and education
versus no intervention . . . . . . . . . . . . . . . .38
Incentive and education versus
no intervention. . . . . . . . . . . . . . . . . . . . . .38
Any booster seat intervention
versus no intervention . . . . . . . . . . . . . . . .40
Discussion / 41
Uncontrolled before-and-after
studies . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Limitations / 50
Conclusion / 52
Figure 2.
37
38
Effects of Booster Seat Distribution
and Education Versus No Intervention
Figure 3.
39
Effects of Incentives and Education
Versus No Intervention
Figure 4.
39
Effects of Law Enforcement
Versus No Intervention
Figure 5.
40
Effects of All Interventions to
Increase Use of Booster Seats
Versus No Intervention
Table 1.
23
Characteristics of Included Studies
Implications for research . . . . . . . . . . . . . . . .52
Table 2.
Implications for practice . . . . . . . . . . . . . . . . .53
Uncontrolled Before and After Studies
43
3
Acknowledgments
We would like to thank the many organizations and individuals who provided us
with information or offered contacts to relevant sources. We thank the Cochrane
Injuries Review, London, England, for their assistance with database searches
and for providing technical support. We gratefully acknowledge the financial
support from AAA Foundation for Traffic Safety.
Page 11 photo credits: Graco Children’s Products, and Michael Mercadante,
TransAnalytics LLC.
4
5
Executive Summary
that the booster seats do what they are intended to do, which is to reduce the
likelihood or severity of injuries in the event of a crash. To examine the effectiveness of booster seat promotion interventions, we undertook a systematic
review of studies, using the Cochrane systematic review method to perform a
meta-analysis.
We began with a search of the Cochrane Injuries Group Specialized Register, the
Cochrane Central Register of Controlled Trials, EMBASE, LILACS, MEDLINE,
the Combined Health Information Database, the National Research Register, the
Science Citation Index, the Science and Social Science Citation Index, transport
research databases, and reference lists of relevant articles. We also contacted
Booster seats in motor vehicles are designed to raise the seated position of
experts in the field. The Cochrane protocol called for including randomized and
children 4–8 years old several inches above the vehicle seat to position the
controlled before-and-after trials.
vehicle’s lap and shoulder belt correctly on the child. Public health and traffic safety agencies recommend the use of booster seats in motor vehicles for
Two reviewers (J.E. and H.E.) independently assessed the quality of the stud-
children until the vehicle’s lap and shoulder belt can fit them properly—typically
ies and extracted data from eligible studies. Final decisions on whether a study
when they have reached a height of 57 inches, have a sitting height of 29 inches,
would be included were reached by consensus among all authors. The included
and weigh about 80 pounds. Using booster seats has been estimated to reduce
studies were categorized and analyzed by type of intervention; outcomes for each
the odds of sustaining clinically significant injuries in a crash by 59 percent for
specific intervention type were compared with outcomes with no intervention;
children aged 4–7, compared with using ordinary vehicle seat belts (Durbin et
then outcomes for all five intervention types were aggregated and compared
al. 2003). Despite this evidence of effectiveness, many children in the United
with the aggregated outcomes for no intervention.
States do not ride in age-appropriate booster seats. For example, Decina and
Lococo (2004) observed child restraint use in six states and found that although
Five studies involving a total of 3,070 individuals met the criteria for inclusion
virtually all infants and 90 percent of children aged 1–3 were restrained in child
in the meta-analysis. All interventions for promoting the use of booster seats
safety seats, only 37.2 percent of children aged 4–8 were in child safety seats
for 4–8-year-olds demonstrated a positive effect (relative risk [RR]=1.43; 95%
or booster seats; the remainder used either the vehicle seat belt alone or no
CI=1.05–1.96). Providing incentives in combination with education demon-
restraint at all.
strated a beneficial effect (RR=1.32; 95% CI=1.12–1.55; n=1,898). Distribution
of free booster seats in combination with education also had a beneficial effect
6
Given the strong evidence on the safety benefits of booster seats, various inter-
(RR=2.34; 95% CI=1.50–3.63; n=380), and so did education-only interventions
ventions have been implemented to increase their use. However, the evidence
(RR=1.32; 95% CI=1.16–1.49; n=563). In one study, the effect of enforcement
on the effectiveness of such interventions has not been as clear as the evidence
of a booster seat law was evaluated; although enforcement showed a positive
7
effect, the association was not statistically significant.
Introduction
Available evidence suggests that several types of interventions to increase the
use of booster seats for children aged 4–8 are effective. Combining incentives (in
the form of discount coupons or gift certificates for booster seats) or distribution
of free booster seats in combination with education increased the acquisition
and use of booster seats, as did education alone. The effect of enforcing booster
seat laws remains unclear. The single study in our meta-analysis that looked at
enforcement found that it did not significantly increase booster seat use. There
is some evidence that legislation has a beneficial effect on the acquisition and
use of booster seats, but it is mainly from uncontrolled before-and-after studies,
which did not meet the criteria for inclusion in the meta-analysis.
Road traffic injuries are a major cause of morbidity and mortality globally. They
are the tenth leading cause of death and the ninth leading cause of the global
burden of disease (Murray and Lopez 1996). The World Health Organization
estimates that more than 1.18 million people are killed and as many as 50 million injured or disabled in road traffic crashes annually (WHO 2004). Unless
preventive measures are taken, road traffic injuries are predicted to become
the third leading contributor to the global burden of disease and injury by 2020
(Murray and Lopez 1996).
The available evidence shows that the fatality rates for road traffic crashes in
developing countries are about six times higher than rates in developed nations
(Nantulya and Reich 2003). Globally, motor vehicle injuries and deaths have been
described as “an issue of immense human proportions, an issue of economic
proportions, an issue of social proportions, and an issue of equity—a problem
that very much affects the poor” (Nantulya and Reich 2002; see also Ross 1999).
The estimated annual direct costs of road traffic crashes are enormous, ranging
from 0.3 percent of the gross national product in Vietnam to almost 5 percent
in the United States (Jacobs et al. 2000).
Children and young people are particularly at risk. The UNICEF Innocenti Re8
9
port on child deaths by injury in rich nations (UNICEF 2001) showed that traffic
L to R: Belt positioning booster, shield booster,
crashes are a leading cause of death among children in the member countries
high-back combination booster.
of the Organization for Economic Cooperation and Development, accounting
for 41 percent of all injury-related child deaths. Motor vehicle injuries involving
children represent a disproportionately large contribution to the global burden
of disease because such injuries result in a large number of years lost because
of premature death or a large number of years lived with disability (Krug et al.
2000).
Children 4–8 years old are more likely to die as a result of motor vehicle crashes
than from other forms of unintentional injuries (CDC 2004). When they outgrow
belt portion of the adult seat belts rides up into a child’s abdomen (Halman et al.
the safety seats designed for younger children, many 4–8-year-olds travel unre-
2002; Hingston 1996; Osberg and Di Scala 1992). Research has demonstrated
strained in motor vehicles or are restrained with adult seat belts without booster
that children 4–8 years old have a significantly lower risk of injury if they are
seats. These practices increase their risk of sustaining serious crash-related
restrained in booster seats rather than by adult seat belts alone (Arbogast et
injuries (Winston et al. 2001).
al. 2005; Durbin et al. 2005; Durbin et al. 2003; Miller et al. 2002; NHTSA 2004;
Winston et al. 2001). It is recommended that children use booster seats until
In addition to mortality and disability, crash-related injuries have been shown to
they are at least 8 years old, unless they are 4’9” or taller (NHTSA 2004).
have enduring negative psychological effects in children (Stallard et al. 2004;
Aitken et al. 2002; Stallard et al. 1998). Even relatively minor childhood injuries
Three types of booster seats are available:
disrupt parents’ ability to work and place significant economic burdens on affected
families as well as on the health system (Osberg et al. 1996). Reducing crash-
1. Belt-positioning boosters, which are designed to be used in vehicles with
related deaths and injuries among 4–8-year-olds requires the implementation
lap and shoulder belts. Some have a high back that provides head support for
of effective strategies to get booster seats into cars and ensure that they are
children who are transported in vehicles that do not have head restraints.
correctly used (Corden 2005; Mickalide et al. 2002; Winston et al. 2001).
There are also backless booster seats for vehicles equipped with head restraints.
Booster seats are recommended by public health and transport safety agencies
(Australia Transport Safety Bureau 2005; UK Department for Transport 2004;
NHTSA 2004; American Academy of Pediatrics 1996). Booster seats help pro-
2. Booster seats with removable shields, which are used without the shield to
make lap and shoulder belts fit better.
tect children from injury and death in crashes by ensuring that the adult seat
10
belt fits properly. Proper fit reduces the risk of “lap belt syndrome” (Mickalide et
3. Combination seats, which are high-back booster seats with an internal har-
al. 2002; Thompson et al. 2001; Durbin et al. 2001), which occurs when the lap
ness that is usually rated for use by children up to approximately 40 pounds.
11
Once the child reaches the upper weight limit of the seat, the harness can
Despite the evidence on the effectiveness of booster seats and the risks associ-
be removed and the seat is then used with the adult lap and shoulder belt
ated with not using them, usage rates for booster seats remain appallingly low.
as a belt-positioning booster seat.
In a study of child safety seat and booster seat use in six states, Decina and
Lococo (2004) reported that although rates of child safety seat use were high
Low- and high-back belt-positioning booster seats have been in use in Europe
for small children (97.3 percent for children younger than 1 year and 90 percent
for nearly 25 years but have been on the market in the United States for about
for children aged 1–3), only 37.2 percent of children aged 4–8 were restrained
15 years (Weber 2000). Booster seat cushions were developed in Sweden and
with any form of child restraint system (i.e., booster seats or forward-facing child
Australia in the mid-1970s to allow children to take advantage of the vehicle’s
safety seats); the remainder either were using adult seat belts (45.5 percent) or
built-in upper and lower torso restraints (NHTSA 2002; Weber 2000). Booster
were entirely unrestrained (17.3 percent). Similarly, in the communities studied
seats are also widely used in Canada, where three primary classifications of
by Ebel et al. (2003), the average rate of booster seat use among children aged
child restraint systems are regulated by law: rear-facing infant restraints, child
4–8 was roughly 16 percent before the implementation of a community-level inter-
restraints, and booster cushions (Dance 2001). Booster cushions are for children
vention. After the intervention, the rate of booster seat use reportedly increased
who have outgrown their child restraint system and weigh at least 40 pounds.
to 26.1 percent in the communities in which the intervention was conducted. In
other words, in the six states Decina and Lococo (2004) studied, slightly more
Booster seats are virtually unavailable in developing countries (UN 2003) other
than one in three children aged 4–8 used age-appropriate restraints, and in the
than in some stores that cater to expatriates and wealthy families. Given the
communities Ebel et al. (2003) studied, fewer than one in five children were
exorbitant prices of booster seats—usually inflated by import taxes—it could
using age-appropriate restraints before the intervention, and only about one in
cost weeks of earnings for an average family to purchase one (Hendrie 2005).
four were using appropriate restraints after the intervention.
Even in a middle-income country such as Brazil, the cost of a booster seat is
far beyond the reach of most average-income families.
Previous reviews of interventions for promoting the use of child restraints have
focused on their use with the youngest children, ranging in age from newborn
Children outgrow child safety seats generally around 40 pounds or 4 years of
to 3 years old—that is, the age group for which child safety seats are recom-
age, at which point they should transition to booster seats. Booster seats are
mended rather than booster seats. Although various interventions have been
designed to raise the seated position of children 4–8 years old several inches
implemented to increase the acquisition and use of booster seats, the evidence
above the vehicle seat to position the vehicle’s lap and shoulder belt correctly on
on the effectiveness of such interventions has not been evaluated systematically.
the child. Despite some claims to the contrary (e.g., Levitt 2005), the effective-
Determining which interventions are effective and which are not and synthesizing
ness of booster seats in protecting children from serious crash-related injuries is
the evidence will help inform future research, guide policy and practice (includ-
well documented. For example, Durbin et al. (2003) reported that booster seats
ing targeting of resources), train health professionals, and facilitate the design
reduced the odds of sustaining clinically significant injuries in a crash by 59 per-
and implementation of effective interventions.
cent for children aged 4–7 and that they were especially effective in reducing
injuries to the abdomen, neck, spine, back, and lower extremities.
12
13
Design and
methods
further research is needed (Wagenaar 1999). The use of explicit, systematic
methods minimizes bias and reduces the effects of chance, thus providing reliable results upon which to draw conclusions and make evidence-based recommendations (Oxman and Guyatt 1993; Antman et al. 1992). To further minimize
bias, both the Cochrane review protocols, which are developed prior to the actual
review, and the reviews themselves are critically examined by external experts
who are not authors and are not involved in the actual review process.
CRITERIA FOR CONSIDERING STUDIES FOR THIS REVIEW
(PROTOCOLS)
In this review we used the Cochrane systematic review method, an objective
Types of studies reviewed
meta-analysis approach that has earned credibility through the integrity and
rigor of its processes and the usefulness of its results. Archie Cochrane, a Brit-
•
ish physician and epidemiologist, was the first to draw attention to the fact that
All randomized controlled studies that investigated the effects of interventions to promote booster seat use
people who wanted to make informed decisions about health programs did not
have ready access to reliable reviews of available evidence. In 1979, Cochrane
•
Controlled before-and-after trials
wrote, “It is surely a great criticism of our profession that we have not organized
a critical summary, by specialty or subspecialty, adapted periodically, of all rel-
Types of participants
evant randomized controlled trials” (Cochrane 1979). Cochrane believed that
reviews of research evidence should be prepared systematically and updated
•
periodically.
Policy makers, planners, practitioners, consumers, and researchers are often
Studies in which subjects were children 4–8 years old or individuals who
transport children in that age group in motor vehicles.
Types of interventions
inundated with information from numerous studies. Systematic reviews help in
the efficient integration of valid information and provide a basis for rational deci-
Legislative/enforcement, educational, and promotional measures to increase
sion-making (Mulrow 1994). Cochrane reviews can be used to establish where
acquisition or use of booster seats for 4–8-year-olds traveling in motor vehicles,
the effects of health interventions are consistent, where research results can be
including:
applied across populations and settings, and where effects may vary significantly
(Oxman 1993; Sacks et al. 1987; L’Abbe et al. 1987; Thacker 1988). They can
demonstrate where sufficient evidence is lacking and thus identify areas where
14
•
Primary enforcement of booster seat laws: a driver can be stopped, cited,
and fined for failure to comply with a booster seat law (Chang 2002).
15
•
Community-wide information and enhanced enforcement campaigns: tar-
•
geted information about booster seats is delivered to a community, usually
Crash-related injury rates in intervention groups compared with control
groups of 4–8-year-olds
defined geographically. These campaigns use mass media, information
and publicity, booster seat displays in public places, public demonstrations
•
of correct use, and special enforcement strategies, such as checkpoints,
Proportion of 4–8-year-olds who were observed using booster seats while
riding in motor vehicles
dedicated law enforcement officials, and alternative penalties (e.g., verbal
or written informational warnings instead of citations).
•
Reported use of booster seats by persons who transport children (such selfreports constitute weak evidence of effectiveness)
•
Booster seat distribution and education programs: booster seats are provided
to parents on loan, as low-cost rentals, or as giveaways. The rationale is
SEARCH STRATEGY FOR IDENTIFICATION OF STUDIES
that parents who cannot afford booster seats and those who have a limited
•
understanding of their benefits might be more likely to use them if financial
We searched numerous electronic databases in various categories (the search
assistance and adequate information are provided.
terms used with each database are listed in Appendix 1):
Incentive and education programs: parents are rewarded for obtaining and
Health
using booster seats, or direct rewards are provided to children for using
them. Incentives may also involve the distribution of discount coupons to
•
Cochrane Injuries Group’s Specialized Register
•
Cochrane Central Register of Controlled Trials (CENTRAL)
•
MEDLINE
•
EMBASE
•
Combined Health Information Database (CHID)
•
National Research Register
offset part of the cost of a booster seat. Incentive programs typically involve
educational components of varying intensity and may include one-on-one
counseling (Zaza et al. 2001).
•
Education-only programs: information about booster seats and relevant skills
is provided to parents or children. Information provides the foundation for
moving people toward behavior change, and some experts say this constitutes an essential component of all interventions for increasing booster seat
use (Ramsey et al. 2000; Simpson et al. 2002).
Types of outcome measures
Transportation
•
Crash-related death rates in intervention groups compared with control
groups of 4–8-year-olds
16
TRANSPORT (incorporates TRIS, ITRD, TRANSDOC, and NTIS)
17
•
TRANSDOC (from the European Conference Ministers of Transport)
•
Dissertation Abstracts
•
National Technical Information Service (NTIS)
•
National Safety Council
•
Transport Research Information Service (TRIS)
•
Online Computer Library Center (OCLC)
•
International Transport Research Documentation (ITRD)
•
Internet
•
Australian Transport Index (formerly ARRB and ATRI)
•
The Grey Literature (http://www.nyam.org/library/grey.shtml)
•
University of Michigan Transport Research Institute (UMTRI)
To obtain information on completed as well as ongoing trials, we contacted injury
prevention programs, transport research institutes, safety institutes, and other
•
Society of Automotive Engineers (SAE)
organizations and practitioners with diverse roles in vehicle occupant protection.
In addition, reference lists were examined for relevant studies or reports.
•
University of North Carolina Highway Safety Research Center (UNHSRC)
METHOD OF THE REVIEW
•
Institute of Transportation Engineers (ITE), University of California,
Berkeley
Educational/psychological
Selection of studies
Two reviewers (J.E. and H.E.) used predefined selection criteria to screen titles
and abstracts of relevant articles to assess their eligibility for inclusion in the
•
PsycInfo
review. For trials that were potentially relevant to the review, copies of the reports
were obtained for further assessment. Those that met the selection criteria were
•
Educational Resources Information Center (ERIC)
assessed for methodological quality by the reviewers. Disagreements were
resolved by discussion and consensus among all four coauthors. The following
•
18
The Campbell Collaboration’s Social, Psychological, Educational, and Crimi-
criteria were used to assess the methodological quality of potentially eligible
nological Trials Register (SPECTR)
studies:
General
Randomized controlled trials
•
1. Concealment of allocation (according to section 6 of the Cochrane review-
Science (and Social Science) Citation Index
19
ers’ handbook; available at http://www.cochrane.dk/cochrane/handbook/
2. Contemporaneous data collection (or data collected at similar time periods)
hbook.htm):
for both control and study sites:
• Adequate if the answer was “yes”
• Adequate if the answer was “yes”
• Unclear if not reported or not clear from report
• Unclear if not reported or not clear from report
• Inadequate if the answer was “no”
• Inadequate if the answer was “no”
2. Comparability between intervention groups with respect to baseline charac-
Data collection
teristics, such as injury rates, death rates, and frequency of booster seat use:
A standardized data abstraction form was used to record data from eligible
• Adequate if no substantial differences were present
studies in four areas:
• Unclear if not reported or not known whether there were substantial
differences
•
Type of study design
•
Types of participants and settings
•
Interventions
•
Outcome measures
• Inadequate if a substantial difference existed
Controlled before-and-after studies
We used the quality criteria adopted from the Cochrane Effective Practice and
Organization of Care (EPOC) methods (available at http://www.epoc.uottawa.
ca/).
For the studies we included in the meta-analysis, we requested any missing
1. Baseline comparability between study and control sites with respect to injury
information from the study authors or relevant contact individuals, groups, or
rates, death rates, and frequency of booster seat use:
organizations.
• Adequate if the answer was “yes”
Data analysis
• Unclear if not reported or not clear from report
RevMan version 4.2.8 (Cochrane Collaboration 2005) was used for statistical
analysis. To determine the effects of the different types of booster seat promo-
• Inadequate if the answer was “no”
20
tion interventions, we categorized and analyzed data by type of intervention
21
Multiple intervention
strategies
Notes
no intervention; and 4) enforcement versus no intervention.
Study is quite old
(1987)
tion and education versus no intervention; 3) incentives and education versus
Follow-up interval very
brief at 2 weeks
were identified and examined: 1) education versus no intervention; 2) distribu-
Booster seats not
specifically mentioned,
but booster seat use
confirmed by author
and compared each intervention type to no intervention. Four intervention types
To estimate the combined effect of all booster seat promotion interventions as
compared with no intervention, we aggregated the data from studies of all four
intervention types and compared all intervention group data with all control
group data. For this, we used the random effects model, which accounts for the
heterogeneity inherent in combining studies of different interventions and gives
a relatively conservative estimate of the size of the effect.
22
Methods
Controls received no
intervention
Observed booster seat
use increased 58%
Educational efforts
included educating
physicians and other
health providers on the
need for child restraint
counseling. Educational
messages were
provided to the target
population through
TV, radio, newsletters,
brochures and flyers,
and classes. Coupons
for discounted booster
seats were distributed.
Parents of children
4–8 years old
and the children
themselves residing
in four intervention
communities
group and the control group that were not accounted for in the study.
Author, Year
(Country)
the results may be biased as a result of differences between the intervention
Table 1. Characteristics of Included Studies
results may be influenced by chance. It does not describe the extent to which
Participants
2.0 and 4.0. This probability range describes the extent to which the observed
Nonrandomized
prospective controlled
community trial.
Allocation concealment
was adequate. Had two
observers per vehicle,
so interobserver
variation was not an
issue. The observers
were unaware of the
outcome status
is a 95 percent probability that the true relative risk actually does fall between
Ebel et al., 2003
(USA)
risk were 3.0 and the 95 percent confidence interval spanned 2.0 to 4.0, there
3. Control group (no
intervention)
which the true relative risk probably falls. For example, if the calculated relative
2. Education aimed at
modifying
the behavior of
preschool children with
regard to child restraint
use
acquire and/or use booster seats. The confidence interval defines a range within
Concealment of
allocation:
unknown
Interventions
that the intervention group was three times more likely than the control group to
Method of
randomization:
unknown
and/or use a booster seat. For example, a relative risk of 3.0 would indicate
1. Enforcement
intervention based on
letters to parents or
guardians reinforcing
existing child restraint
law
seat, relative to the probability that a person in the control group will acquire
Preschool children 3–5
years old in Newcastle,
New South Wales,
Australia
group receiving the intervention under study will acquire and/or use a booster
Randomized trial
Outcomes
context, the relative risk is used to assess the probability that a member of the
Bowman et al. 1987
(Australia)
type, with 95 percent confidence intervals, using the fixed effect model. In this
Restraint use of
children in the
educational intervention
group increased from
60.6% to 75.0%
We calculated relative risks in the analysis of the effects of each intervention
23
24
Stevens, 2000
(USA)
O’Neil et al., 2005
(USA)
Johnston et al., 2000
(USA)
Randomized trial.
Allocation concealment
adequate (different
days). Not a blinded
observer
Blinded observers
Randomized trial
(clustered)
Nonrandomized trial
(clustered). Allocation
concealment unclear.
Blinding unclear.
Home visit by Head
Start staff to educate
families on booster seat
use, smoke alarms, and
storage of household
chemicals. Intervention
participants received
supplies
Children received
age-appropriate
educational classes
in the centers and
schools. Interventions
for parents were either
distribution of booster
seats and education/
skills training; incentive
to purchase a seat and
education/skills training;
or no information
(control group)
Participants either
given pamphlet (P)
and coupon (C) for
seat, just a pamphlet,
just a coupon, or no
intervention (control
group)
Parents of children 4–5
years old enrolled in
Head Start programs
Parents of children
4–6 years old and the
children themselves
attending 9 day care
centers and preschools
in Indianapolis, Indiana
Parents of children
3.5–8 years old and
weighing 35–80 pounds
entering a retail toy
store in Virginia
Purchase of booster
seat increased 34%
for the C+P group,
38% for P, 41% for C,
and 3% for the control
group. All respondents
self-reported using the
booster seat every time
child traveled
After 6 months,
observed booster seat
use increased from
42.6% to 66.7% in the
distribution+education
group; from 34.7%
to 48.8% in the
incentive+education
group; and from 39.4%
to 52.2% in the control
group
Self-reported “always”
used booster seat
Observed booster seat
presence from 0 to
21.5%.
Relatively brief followup interval of 30 days.
Unclear whether study
had sufficient statistical
power
Insufficient statistical
power because of high
attrition
Mostly low-income
families
DESCRIPTION OF STUDIES
Study selection
Our search strategy identified 1,350 published and unpublished reports that were
topically related to child motor vehicle occupant protection. This long list was
narrowed down to 62 reports that dealt with strategies to promote use of child
restraints. Twelve of these specifically dealt with booster seat interventions, and
of these 12, only five met the rigorous criteria for inclusion in the review.
A total of 3,070 individuals were involved in the five studies. Four of the studies
were conducted in the United States (Ebel et al. 2003; Johnston et al. 2000;
Stevens 2000; O’Neil et al. 2005) and the other in Australia (Bowman et al.
1987). The studies are described below, and additional information on the stud-
ies’ characteristics is provided in Table 1.
Of the 12 studies that specifically dealt with booster seat interventions, the
seven that were excluded did not qualify primarily because they lacked enough
information to adequately assess the intervention. From the larger group of 62
reports that dealt with promoting use of child restraints, eight studies were identi-
fied as ongoing and may be eligible for inclusion when the Cochrane review is
updated (see Appendix 2). Data from 12 uncontrolled before-and-after studies
were also excluded from the meta-analysis, but the studies’ characteristics and
findings are summarized in Table 2 to provide a broad view of the research and
evidence.
Characteristics of included studies
The unit of analysis varied among the studies. Stevens (2000) studied indi-
viduals, and Bowman et al. (1987) used both individuals (parents of preschool
children) and preschools as the units of analysis. The other three studies (Ebel
25
et al. 2003; Johnston et al. 2000; O’Neil et al. 2005) used a clustering based on
tion was recorded by a single observer on one morning before the interventions
communities, schools or preschools, or day care centers. All five studies were
and again immediately after. The percentage restraint use before the intervention
controlled trials; three were non-randomized (Bowman et al., Ebel et al., and
was calculated for each preschool. Preschools were then assigned randomly
Johnston et al.). Four of the studies relied on observed use of booster seats as
to a control or an intervention group, after matching for restraint use. Fifteen
the outcome measure (Ebel et al., O’Neil et al., Bowman et al., and Johnston et
preschools were assigned to each of the control, educational intervention, and
al.). Stevens used self-reports as the outcome measure and corroborated the
law enforcement intervention groups.
self-reports with actual purchases of booster seats by examining the number
of discount coupons used at the store. The interval between baseline and pos-
Research assistants visited the preschools in the two intervention groups to
tintervention follow-up ranged from 2 weeks to 15 months. The sections below
deliver and explain the use of the intervention materials. The enforcement inter-
contain detailed discussions of the characteristics of each study.
vention used threats of random police checks and fines to attempt to increase
restraint use. Copies of a letter from the Chief Inspector of Police in the New-
Bowman et al., 1987 (Newcastle, Australia)
castle District were handed individually to parents by the preschool director. The
letter outlined legislation concerning the wearing of safety restraints by children.
The purpose of this study was to implement and compare the effectiveness of
It warned parents that police would be conducting random checks in the area
two interventions to increase the use of safety restraints with preschool children
and that parents whose children were not adequately restrained would be fined.
aged 3 to 5. Bowman et al. did not specifically mention booster seats in their
Police were not conducting checks but had agreed to include the warning in the
report, but recommendations in Australia at the time of the study (as now) were
letter to increase the parents’ perception of a threat of enforcement. The letter
for children in the 3–5 age group to move into booster seats as an intermedi-
also included information about the types of child restraints available and their
ary step before graduating to adult seat belts. We contacted the first author of
approximate cost. An accompanying pamphlet supplied general information
the report and confirmed that the study evaluated use of booster seats. One
about the use of child restraints. Posters and reminder cards with the same
of the interventions in the study involved a law enforcement strategy aimed at
warning of police checks and possible fines were also used. Each preschool
parents; the other was an educational intervention aimed at preschool children.
was supplied with three posters, which were displayed prominently. Reminder
The educational intervention was designed to address two issues: children’s
cards were pinned to the children’s clothing or placed in their lunch boxes on
resistance to the use of restraints and children’s passive acceptance of being
the intervention days during the two-week follow-up period.
unrestrained. Children were taught by their teachers to insist on using a restraint
when traveling in the car and to persist until their parents took action to ensure
In the educational intervention, the materials were presented to preschool di-
that they were properly restrained.
rectors in kit form along with a detailed explanation of their use. The materials
included copies of six different drawings featuring cartoon characters; two brief
26
Study subjects were children attending 45 preschools randomly selected from the
songs, written to well-known tunes; a rubber stamp that read “seat belt safety”;
telephone directory and their parents. Trained observers recorded the restraint
and two modified lap seat belts that were fitted to preschool chairs. Suggestions
status of children as they arrived at school. At each preschool, restraint informa-
were made for ways in which the supplied materials might be used, but it was
27
left to the individual preschool teachers to create their own programs.
Ebel et al., 2003 (Seattle, Washington, USA)
and providing alternatives for automobiles with lap-only belts
•
Discount booster seat coupons
•
Car seat training programs and in-services for health care providers,
child care providers and educators, law enforcement, emergency medi-
This study assessed the effectiveness of a multifaceted community booster seat
cal service personnel, and child passenger safety advocates (Ebel et
campaign, using a prospective, non-randomized, controlled community inter-
al. 2003, 881)
vention design. The campaign was initiated in four communities in the greater
Seattle area between January 2000 and March 2001. Eight communities in
The outcome measure was rates of booster seat use observed at 83 child care
Portland, Oregon, and Spokane, Washington, served as control sites. Ebel et
centers and after-school programs 15 months after the start of the campaign.
al. described the intervention as follows:
Booster seat use rates were adjusted for child’s age, driver’s seat belt use, and
driver’s gender.
Booster Seat Campaign Elements
•
Community coalition of agencies and organizations to promote the use
Johnston et al., 2000 (Washington State, USA)
of booster seats
•
•
Citizen advisory group of parents and caregivers to provide feedback on
This study assessed the effects of an injury prevention program delivered by
campaign messages and materials and to develop strategies to ensure
school-based home visitors to low-income families whose children were attend-
community involvement
ing preschool enrichment programs in Washington State. Study participants
Broad-based community education program to increase knowledge and
were the families of children 4–5 years old living in a defined geographic area
awareness of the importance of booster seat use, which included:
and enrolled in Head Start or Washington State’s Early Childhood Education
– Newspaper articles
and Assistance Program between January and June 1998. Of the 258 families
– Organization and group newsletter articles
enrolled at the intervention sites, 213 (82.6%) completed both baseline and
– Booster seat Web site
postintervention assessments. Of the 160 families at the comparison sites, 149
– Tip sheet, brochures, and flyers in multiple languages
(93.1%) completed both baseline and postintervention assessments. Analysis
– Telephone information line where parents can call for materials and
was restricted to those families that completed both assessments. Case work-
with questions about booster seats and car seats
28
ers administered a baseline home safety assessment to participating families
– Resource kits for preschools and health care providers
and recorded availability of booster seats in motor vehicles owned by the family.
– Radio public service announcements
Families in the intervention group were offered educational materials and free
– Television public service announcements
child safety equipment, including age-appropriate car safety restraints, depending
– Local news reports
on the results of the home inspection (195 families received such equipment).
– Educational programs to address barriers to booster seat use, including
Families in the comparison group received only written information encouraging
defining types of booster seats, identifying where devices are available,
them to purchase needed safety equipment, including booster seats. Outcome
29
data were obtained by the same case workers who had originally enrolled the
a marked-off area of the parking lot of each participating facility. As vehicles
families; they returned 3 months after enrollment to repeat the home safety as-
approached the facility for the morning drop-off, the drivers were stopped, and
sessment. The outcome measure was self-reported use of booster seats. Avail-
those who were identified as potential study participants were asked if they would
ability of booster seat was confirmed at the home visit by the case worker.
be interested in participating in the study. If they were, informed consent was
obtained, and the driver completed a questionnaire to provide personal demo-
O’Neil et al., 2005 (Indianapolis, Indiana, USA)
graphic information and data on their knowledge, attitudes, and beliefs involving
the use of booster seats, seat belts, and seating position in the vehicle. While
This was a blinded randomized controlled trial conducted in day care centers and
the driver completed the survey, the observer noted the type and use of child
preschools to evaluate methods of increasing booster seat use for children 4–6
safety seats, booster seats, seat belts, and seating position in the vehicle.
years old. The study selected nine facilities and assigned them to one of three
groups: distribution and education, incentive and education, or control group. The
The child passenger’s height and weight were measured and recorded. Obser-
education component, based on the health belief model of behavioral change
vations were conducted and questionnaires were completed again at interven-
(Glanz et al. 2002), was the same in both intervention groups. Parents in the
tion and control sites 1 month and 6 months after the intervention program was
distribution and education group were taught how to correctly install and use a
completed. Personnel at the sites did not know in advance when observers
booster seat in their vehicle. At the end of the session the parents were offered
would be present, and observers remained blinded to which were intervention
a free booster seat. Their children received a separate educational presentation
or control sites. The main outcome measure was the observed use of booster
on why children need to be buckled up in a booster seat and sit in a rear seating
seats at the 1- and 6-month follow-ups. Our Cochrane analysis was restricted
position in the vehicle. Educational information and materials were based on
to the 6-month postintervention point. A total of 207 children 4–6 years old were
the Boost America program, using the Blue’s Clues format with songs, coloring
enrolled and observed at baseline, and 136 of them were observed at the 6-
activities, and a brief question-and-answer period.
month postintervention follow-up (a 34.3 percent loss to follow-up).
Parents in the incentive and education group were similarly taught about the
Stevens, 2000 (Virginia, USA)
importance of booster seats and how to use them but were not offered free
booster seats. They were informed that if they were observed with a child using
Stevens conducted a field study with a volunteer sample of 128 participants made
a booster seat at the 1-month and 6-month observations they would be entered
up of customers walking into a retail toy store in a community in southwestern
into a drawing to win a gift certificate. The control group received educational
Virginia. All participants had a child who was 3.5 to 8 years old, weighed 35 to
materials through an informed consent document that provided information typi-
80 pounds, and was not in a booster seat at baseline. Stevens sought to deter-
cally given during a primary care health maintenance visit.
mine whether 1) pamphlets with information on booster seat use and coupons
providing a sizable discount on booster seats would encourage participants to
30
On the day of the baseline observation and survey, certified child passenger
purchase booster seats, and 2) the pamphlets would increase participants’ risk
safety technicians and their assistants were stationed at the entrance and in
perception. The participants were randomly assigned to one of four groups:
31
pamphlet and discount coupons, pamphlet only, discount coupon only, and no
(40.0 percent). The percentage of African Americans in the three groups was
intervention. The pamphlet contained a warning label, a true story of a child
apparently unrelated to low income, as the education and incentive group had
who was killed because he was restrained in an adult seat belt instead of a
the lowest percentage receiving WIC* funding (21.7 percent, compared with
booster seat, and statistics on and consequences of non-use of booster seats.
25.3 percent for the education and distribution group and 47.8 percent for the
The coupon’s value of $30 represented 30–60 percent off the cost a high-back
control group; p=0.006). The control group was younger on average than the
booster seat. Outcome measures were change in participants’ risk perception
intervention groups (mean age, 32.3 years, compared with 35.1 years for the
and whether or not they purchased a booster seat.
education and distribution group and 36.8 years for the education and incentive
group; p=0.010). Stevens did not discuss the demographic characteristics of
METHODOLOGICAL QUALITY OF INCLUDED STUDIES
the study population but noted that the retail store was in an affluent area. No
comparison of the two intervention arms was discussed, although the age and
Intergroup comparability of sociodemographic characteristics
gender of the parents were noted.
Ebel et al. matched the four intervention communities with the eight control
Blinding
communities using per capita income and population size and used statistical
methods to adjust for variables such as the child’s age and the driver’s gender
In the Bowman et al. study, observations were recorded on one morning at
and seat belt use. Bowman et al. did not report the sociodemographic character-
each preschool by a single observer. The authors discussed the reliability of
istics of the study population. They only indicated that preschools were matched
observations but did not report whether the observers were blinded. The Ebel
for restraint usage to ensure that no group was biased with a disproportionate
et al. study used teams of two or more observers to conduct observations, and
number of high or low restraint rates. Johnston et al. compared the interven-
blinding status was not mentioned. In the Johnston et al. study, one case worker
tion and control communities on the basis of child age, gender, race/ethnicity,
was assigned to one family for both pre- and postintervention assessments in
parental employment, primary language, single- or dual-parent home, child’s
both the intervention and control communities; the authors did not report whether
educational disability, and median household income. O’Neil et al. compared
these case workers knew the purpose of the evaluation or which communities
the demographic characteristics of the control and intervention groups and
were in the intervention and control groups. O’Neil et al. indicated that observers
noted a difference in racial composition (p=0.002), with the education and in-
did not know which day care centers and preschools were in the intervention
centive group having a higher proportion of African Americans (63.2 percent)
and control groups. Stevens was both the investigator and the observer and
than the education and distribution group (34.7 percent) and the control group
knew which subjects were in the intervention and control groups, so blinding
was not possible.
*The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC)
is a federally funded program for low-income pregnant, postpartum, and breast-feed-
Social desirability
ing women and young children up to age 5. WIC participants receive food checks and
nutrition counseling.
32
Social desirability bias may be introduced in a study when the outcome measure
33
relies on self-report (Adams et al. 2005). Respondents, eager to please their
enthusiasm and aggressive telephone follow-ups, calling subjects as many as
interviewer, may give responses that they believe the interviewer would view as
four times to obtain outcome data.
socially desirable or answers they believe the interviewer would like to hear in
order to prove that the research activity was effective. The Johnston et al. and
Separation of interventions
Stevens studies may have been susceptible to social desirability bias because
they relied on self-reports—and using booster seats was clearly the desired
Stevens distinguished between two factors together (pamphlet plus coupon),
behavior. Stevens, however, corroborated the self-reports of booster seat pur-
pamphlet only, coupon only, and one group with no intervention at all. John-
chases by confirming redeemed coupon numbers at the store. In the Johnston
ston et al. compared an intervention involving information and distribution of
et al. study, the case worker confirmed availability of a booster seat at the home
seats with one involving information only. Bowman et al. used two intervention
visit, but self-reported use of the booster seat was not verified. Bowman et al.,
arms—teaching children about the importance of restraints, which they hoped the
Ebel et al., and O’Neil et al. measured booster seat use via direct observation,
children would pass on to their parents, and threats of enforcement of existing
so social desirability bias is not likely to have been an issue.
restraint laws for parents—and a non-placebo control group. They provided the
educational intervention kits to preschools and made suggestions on ways in
Loss to follow-up
which the supplied materials might be used but left it to the individual preschool
teachers to create their own programs. Although it was noted that preschools
Loss to follow-up for the postintervention assessment was variable among the
were visited twice during the 2-week intervention to ensure that interventions
studies. In the Johnston et al. study, a high proportion of intervention-eligible
were being implemented correctly, implementation strategies across the 45
families enrolled in and completed the study; however, the authors did not con-
preschools may have varied. O’Neil et al. used two intervention arms and com-
duct a comparative analysis of those who dropped out of the study or those who
pared distribution and education; incentives and education; and a nonplacebo
chose not to participate versus those who did participate. Not knowing anything
intervention control. The Ebel et al. campaign was a community-based interven-
about the families who chose not to participate meant that it was not possible
tion that used multiple intervention strategies, including community mobilization
to determine whether they differed from participants; similarly, the families that
and involvement. Because the purpose of the study was to evaluate the overall
completed the study may have been different from the families that did not com-
impact a community-based campaign had on rates of booster seat use through-
plete the study, but no data were collected on this. O’Neil et al. had a significant
out the community, the effects of different aspects of the intervention were not
loss to follow-up—about one-third of the participants. Of these, 20 percent of
distinguishable. Distributing booster seats might have been more effective than
the children moved from the study facilities, and a number of participants lost
the brochures and flyers, for instance, but the analyses could not reveal such
interest. Ebel et al. observed booster seat use at the community rather than
distinctions.
the individual level, so loss to follow-up was not an issue. Similarly, for Bowman et al., who observed 740 preschool children at baseline and 751 after the
Measurement issues
intervention, loss to follow-up was not an issue. Amazingly, Stevens had no loss
to follow-up among the 128 subjects in her study, which she attributes to her
34
Overestimation of the effectiveness of the specific interventions studied may
35
Results
have occurred in both the O’Neil et al. study and the Ebel et al. study. Study
subjects may have heard about the passage of new booster seat laws from
sources other than those related to the intervention, which may have increased
awareness and led participants in both the intervention and control groups to
acquire and use booster seats.
A complicating factor in the measurement of booster seat use is that the only
objective way to ensure “age-appropriateness” is to measure the child’s height
and weight. Few studies have done this, because of the time required and because of concerns about recruiting and retaining participants in a time-consuming
and obtrusive process. The O’Neil et al. study was the only one of the five that
measured the height and weight of participating children; the others relied on
All five studies reported on the frequency of booster seat use (observed or re-
reports from parents or caregivers.
ported) after the interventions.
Theoretical framework
EDUCATION VERSUS NO INTERVENTION
In the Bowman et al. study, 173/231 (75%) participants in the education-only
Two of the studies clearly relied on strong behavior change theories in designing
arm used booster seats at 2 weeks, compared with 161/268 (60%) participants
their studies. Ebel et al. used the precede-proceed model, which attempts to
in the no intervention group (Figure 1). Stevens showed that participants in the
effect behavioral change by identifying predisposing, enabling, and reinforcing
education arm of her study were more likely to purchase booster seats (12/32,
factors (Green and Kreuter 2004). The design of the O’Neil et al. study was
38%) than were those in the control group (1/32, 3%) 1 month. Combined results
based on the health belief model, which establishes leverage points that can
from both studies show a beneficial outcome in favor of education (relative risk
be influenced, such as perceived susceptibility, perceived severity, perceived
[RR]=1.32; 95% CI=1.16–1.49; n=563).
benefits of taking action, perceived barriers to action, cues to action, and
self-efficacy (Glanz et al. 2002). Stevens relied generally on a combination of
theories derived from the hazard and warnings literature as well as the concept
that increased risk perception (in this case, perceived risk of injury severity) will
motivate behavior change. Johnston et al. and Bowman et al. did not indicate
that theory had been integrated into their study design or implementation.
Figure 1. Effects of Education Versus No Intervention
Review:
Comparison:
Outcome:
Study
or sub-category
Interventions for promoting booster seat use for 4- 8 year olds travelling in motor vehicles.
01 Education versus No Intervention
01 Booster seat use (reported or observed)
Treatment
n/N
Control
n/N
RR (fixed)
95% CI
Weight
%
RR (fixed)
95% CI
Bowman 1987
Stevens 2000
173/231
12/32
161/268
1/32
99.33
0.67
1.25 [1.10, 1.41]
12.00 [1.66, 86.94]
Total (95% CI)
263
300
100.00
1.32 [1.16, 1.49]
Total events: 185 (Treatment), 162 (Control)
Test for heterogeneity: Chi² = 5.57, df = 1 (P = 0.02), I² = 82.1%
Test for overall effect: Z = 4.33 (P < 0.0001)
0.01
0.1
Favors control
36
1
10
100
Favors treatment
37
the participants in the no intervention group (12/23, 52.2%). The combined re-
DISTRIBUTION AND EDUCATION VERSUS NO INTERVENTION
sults from the three studies (Figure 3) indicate a beneficial effect of incentives
In the Johnston et al. study, 42/195 (22%) participants in the education and
and education in increasing booster seat use compared with no intervention
distribution arm had obtained child safety seats at 3 months, compared with
(RR=1.32; 95% CI=1.12–1.55; n=1,898).
7/132 (5%) in the no intervention group. In the O’Neil et al. study, 20/30 (67%)
participants in the combination group used booster seats at 6 months, compared
Figure 3. Effects of Incentives and Education Versus No Intervention
with 12/23 (52%) participants in the control group—a larger proportion, but the
difference was not marked (RR=1.28; 95% CI=0.80–2.04). As shown in Figure
Review:
Comparison:
Outcome:
2, the combined results from both studies show a beneficial effect in combin-
Study
or sub-category
ing distribution and education compared with no intervention (RR=2.34; 95%
Ebel 2003
O'Neil 2005
Stevens 2000
CI=1.50–3.63; n=380).
Total (95% CI)
Interventions for promoting booster seat use for 4- 8 year olds travelling in motor vehicles.
03 Incentive+Education versus No Intervention
01 Booster seat use (reported or observed)
Treatment
n/N
184/705
20/41
11/32
Weight
%
RR (fixed)
95% CI
215/1065
12/23
1/32
91.27
8.19
0.53
1.29 [1.09, 1.54]
0.93 [0.57, 1.54]
11.00 [1.51, 80.28]
1120
100.00
778
Control
n/N
RR (fixed)
95% CI
Figure 2. Effects of Booster Seat Distribution and Education Versus No Intervention
0.01
Review:
Comparison:
Outcome:
Study
or sub-category
Control
n/N
0.1
1
Favors control
Interventions for promoting booster seat use for 4- 8 year olds travelling in motor vehicles.
02 Distribution+Education versus No Intervention
01 Booster seat use (reported or observed)
Treatment
n/N
RR (fixed)
95% CI
Weight
%
1.32 [1.12, 1.55]
Total events: 215 (Treatment), 228 (Control)
Test for heterogeneity: Chi² = 6.20, df = 2 (P = 0.04), I² = 67.8%
Test for overall effect: Z = 3.30 (P = 0.0010)
RR (fixed)
95% CI
Johnston 2000
O'Neil 2005
42/195
20/30
7/132
12/23
38.06
61.94
4.06 [1.88, 8.76]
1.28 [0.80, 2.04]
Total (95% CI)
225
155
100.00
2.34 [1.50, 3.63]
10
100
Favors treatment
ENFORCEMENT OF LAW VERSUS NO INTERVENTION
Only the Bowman et al. study compared enforcement of a booster seat law with
Total events: 62 (Treatment), 19 (Control)
Test for heterogeneity: Chi² = 8.44, df = 1 (P = 0.004), I² = 88.1%
Test for overall effect: Z = 3.77 (P = 0.0002)
no intervention. As shown in Figure 4, the study demonstrated no marked dif0.01
0.1
Favors control
1
10
100
ference in use of booster seats in the intervention (158/252, 63%) and control
Favors treatment
(161/268, 60%) groups (RR=1.04; 95% CI=0.91–1.20; n=520).
INCENTIVE AND EDUCATION VERSUS NO INTERVENTION
In the Stevens study, a larger proportion of participants in the combined intervention group than in the no intervention group had purchased booster seats at
the 1-month follow-up (11/32, 34%, compared with 1/32, 3%). In the Ebel et al.
study, 184/705 (26.1%) participants in the combined group used booster seats,
compared with 215/1,065 (20.2%) in the no intervention group. Booster seat use
rates were adjusted for child’s age, driver’s seat belt use, and driver’s gender.
The O’Neil et al. study, however, showed no difference in the use of booster
seats at 6 months among participants in the treatment arm (20/41, 48.8%) and
38
Figure 4. Effects of Law Enforcement Versus No Intervention
Review:
Comparison:
Outcome:
Study
or sub-category
Interventions for promoting booster seat use for 4- 8 year olds travelling in motor vehicles.
04 Enforcement of law versus No Intervention
01 Booster seat use (reported or observed)
Treatment
n/N
Control
n/N
RR (fixed)
95% CI
Weight
%
RR (fixed)
95% CI
Bowman 1987
158/252
161/268
100.00
1.04 [0.91, 1.20]
Total (95% CI)
252
268
100.00
1.04 [0.91, 1.20]
Total events: 158 (Treatment), 161 (Control)
Test for heterogeneity: not applicable
Test for overall effect: Z = 0.61 (P = 0.54)
0.01
0.1
Favors control
1
10
100
Favors treatment
39
Discussion
ANY BOOSTER SEAT INTERVENTION VERSUS NO
INTERVENTION
The combined results of all five studies (Figure 5) showed a marked beneficial
effect on booster seat use when an intervention was used, compared with no
intervention (RR=1.43; 95% CI=1.05–1.96; n=3,070).
Figure 5. Effects of All Interventions to Increase Use of Booster Seats Versus No Intervention
Review:
Comparison:
Outcome:
Study
or sub-category
Bowman 1987
Ebel 2003
Johnston 2000
O'Neil 2005
Stevens 2000
Interventions for promoting booster seat use for 4- 8 year olds travelling in motor vehicles.
05 Any booster seat promotion campaign versus No Intervention
01 Booster seat use (reported or observed)
Treatment
n/N
331/483
184/705
42/195
40/71
36/96
Contol
n/N
RR (random)
95% CI
Weight
%
161/268
213/1065
7/132
12/23
1/32
33.86
31.98
11.15
20.64
2.37
1550
1520
Total (95% CI)
Total events: 633 (Treatment), 394 (Contol)
Test for heterogeneity: Chi² = 19.47, df = 4 (P = 0.0006), I² = 79.5%
Test for overall effect: Z = 2.28 (P = 0.02)
100.00
RR (random)
95% CI
1.14 [1.02, 1.28]
1.30 [1.10, 1.55]
4.06 [1.88, 8.76]
1.08 [0.69, 1.68]
12.00 [1.71, 84.03]
1.43 [1.05, 1.96]
The benefits of using booster seats for children who are too big for safety seats
designed for toddlers but too small to use adult seat belts have been widely
discussed in the literature (Corden 2005; Mickalide et al. 2002; Winston et al.
2001). Also, barriers to acquiring and using booster seats have been examined
0.01
0.1
Favors Control
1
10
100
Favors Intervention
and documented (Academy for Educational Development 2001; Ramsey et al.
2000). Finding effective ways to translate available knowledge into greater ageappropriate booster seat use remains a challenge for traffic safety and public
health agencies.
Opportunities to increase booster seat acquisition and use fall into four categories: legislation requiring use of booster seat, enforcement of booster seat laws,
distribution of booster seats (or incentives to purchase them), and educational
interventions. Our initial search produced a total of 1,350 reports that were related to child motor vehicle occupant protection, of which 12 dealt specifically
with booster seats. Of these, only five studies met the criteria for inclusion in
the meta-analysis.
Our analyses show that interventions that combine education with either incentives to acquire booster seats (in the form of discount coupons) or distribution
of free booster seats have a beneficial effect on acquisition and use of booster
40
41
since any observed differences between pre- and postintervention measures
could have resulted from chance or simply the passage of time. Although these
quasi-experimental studies did not meet the strict criteria for inclusion in the
meta-analysis, they are mentioned and summarized here in order to capture
the totality of evidence regarding booster seat laws.
42
Study
Population
Study
Design
effect. Without comparison groups, however, these findings are uncertain,
Objectives
accurately, threat of enforcement—and four of these demonstrated a positive
Author,
Year
(Country)
before-and-after studies assessed the impact of law enforcement—or, more
Table 2. Uncontrolled Before and After Studies
seat laws that qualified for inclusion in the meta-analysis, five of the uncontrolled
1. Substantial increase in booster
seat use after intervention
56%
54%
57%
59%
No Restraint
Age 4–5
Age 6
Age 7–8
Changes were significant at p<0.01
Pre
3%
5%
2%
0%
3. No differences between levels of
intervention and use of booster
seats
Follow-up done
4–8 weeks after
baseline
All families were
given free booster
seats
Although our search produced only one study dealing with enforcement of booster
Incentive: gift
certificate to local
grocery store
uncontrolled before-and-after design (Table 2).
2. Booster seat use decreased with
age
Intervention
and Follow-up
evaluation of the interventions’ impact. We identified 14 studies that used the
Policy: day care
center policies
changed to
recommend use of
booster seats
of child restraints in motor vehicles, very few programs have involved rigorous
Education: trained
day care staff and
parents about
risks of not using
booster seats
and distributed
pamphlets
in multiple
languages
Although many reports have been published on interventions to increase use
Used focus
groups,
surveys, and
observation
Outcomes
Measured
UNCONTROLLED BEFORE-AND-AFTER STUDIES
Percentage of
children
4–8 years old seen
riding in booster
seats
wish to be as effective as possible but must work within limited budgets.
Three-level
intervention:
for the design and implementation of future interventions, as program planners
Low-income
parents with
children 4–8
years old enrolled
in nine day
care centers
in Providence,
Rhode Island
than incentives. The results of these analyses may have significant implications
Uncontrolled
pretest/posttest
free booster seats with incentives, noting that distribution was more effective
To increase
booster seat
use among lowincome parents
Key Study Results
an effect in the Bowman et al. study. Only O’Neil et al. compared distribution of
Apsler et al.,
2003
(USA)
in both the Johnston et al. and O’Neil et al. studies. Education demonstrated
Booster seat use
Age 4–5
Age 6
Age 7–8
Post
38%
63%
19%
0%
purchases and use of boosters. Distribution of free booster seats was influential
26%
13%
36%
46%
seats. Ebel et al. and Stevens provided discount coupons, which increased
43
44
45
To evaluate
the effect of
locally funded
education and
enforcement
programs
aimed at
increasing child
restraint use
Decina et al.,
1994
(USA)
Foss, 1989
(USA)
To evaluate
the impact
of the Child
Passenger
Safety Initiative
on parents’
knowledge,
use, and
misuse of child
safety seats
Cooper at al.,
2004
(USA)
To assess the
impact of a
communitywide incentive
campaign on
seat belt use
To increase
proper child
restraint use
To increase
appropriate
child car
restraint use
among 4–6
year old rural
schoolchildren
Browning
et al., 1999
(Australia)
Pretest/
posttest;
telephone
survey;
observation
Used
observation and
self-report
Pretest/posttest
with control
group
Quasiexperimental
Used interviews
and observation
Uncontrolled
pretest/posttest
Used
observation,
self-report, and
questionnaire
Uncontrolled
pretest/posttest
Control: None
Target: Children
aged 0–12
Control: Residents
of Abington,
Pennsylvania
Target: Residents
of Tredyffrin
and Haverford,
Pennsylvania
Families with
children aged
0–6 belonging to
vulnerable groups
(minorities,
low-income)
and attending
seven public
hospitals and
health systems in
California
Rural
schoolchildren
4–7 years old
enrolled in
kindergarten, preprimary or year
1 in five schools
in Brunswick,
Harvey, and
Yarloop, Australia,
and the children’s
parents
5-month incentive
campaign aimed
at parents and
children; radio
spots; flyers
One year
educational and
enforcement
intervention.
Included kickoff
events, distribution
of print materials
and promotional
items through
community,
school visits, and
citations
Follow-up done
approximately 1
year after baseline
Education of
parents/caregivers
on proper child
restraints,
distribution of
free and low-cost
seats, trained
physicians/nurses
to teach patients
about proper car
seat use, outreach
component
educated foster
parents and child
welfare workers
about child
passenger safety
Child Passenger
Safety Initiative
Follow-up done
3 months after
baseline
Children received
rewards in school
for reporting
restraint use
Parents received
educational
materials,
vouchers for free
booster seats for
eligible families,
free checking of
child restraints
School-based
intervention:
Percentage of
children aged 0–12
observed using seat
belts
Percentage of “fully
protected” toddlers
Percentage of
toddlers 3–5 years
old observed using
child restraint
Observed use of
booster seats
Reported use of
booster seats for
children aged 4–6
Knowledge of
booster seat safety
law
Percentage of
parents using
offer of free child
restraints check
Parents’ attitudes
Percentage of
children 4–6 years
old seen using
age-appropriate
restraints
Observed use of
child restraints
45%
Pre
79%
69%
Post
90%
57.3% 55.5%
Pre
Post
79.4% 74.6%
Pre
36.5%
27%
33.2%
“Fully protected”
toddlers aged 3–5
Tredyffrin
Haverford
Abington
Post
45.1%
37.5%
33.6%
Post
49.4%
39.4%
38.6%
10.4% 11.9%
Pre
Post
26.8% 36.4%
Findings showed short-term
improvements in seat belt use in
response to radio spots
Age 6–12
Age 0–5
These findings were not statistically
significant
Pre
40.6%
30.5%
38.7%
Child restraint
use in toddlers
aged 3–5
Tredyffrin
Haverford
Abington
Observed booster seat use decreased
between pre- and posttest (p<0.05)
[no data reported]
Drivers
who
reported always
using booster
seats
Drivers
with
knowledge
of child
passenger
safety law
(p<0.05)
Despite 85% of parents believing not
everyone could tell if a child restraint
is properly installed, less than 3%
used the free checking of child
restraints
85% believed not everyone can tell if
a child restraint is properly installed.
40% thought child restraints were too
expensive.
Ageappropriate
restraint
(p<0.0009)
Overall
child
restraint
(p=0.002)
46
47
Murrin, 2004
(USA)
To evaluate
parents’
knowledge and
attitudes about
child passenger
and booster
seat use for
children 4–9
years old
HemmoLotem, 2004
(Israel)
To compare
before-law and
after-law use of
booster seats in
California
To identify
groups and
factors that
influence
booster seat
use
To evaluate an
intervention
program
initiated by
BETEREM
To evaluate
the impact of
intervention
and law on
booster seat
use
Griffin et al.,
2003
(USA)
Cross-sectional
Used data
gathered during
child restraint
inspection
events
Uncontrolled
pretest/posttest
(before and
after law)
Used telephone
surveys
Uncontrolled
pretest/posttest
Used
observation and
interview
Uncontrolled
pretest/posttest
(before and
after passage
of booster seat
law)
Children up to age
6 or weighing less
than 60 pounds
Parents with
children under 15,
including Russianspeaking subset
Members
of ethically,
culturally, and
linguistically
diverse urban and
rural communities
of varying
socioeconomic
status in seven
communities in
California
Enactment of
California law
requiring children
under age 6 or
less than 60
pounds to ride in a
booster seat
Enforcement
component, media
campaign;
details not
provided
Follow-up done 1
year after baseline
Intervention
spanned the
passage and
enforcement
of California’s
booster seat law
Community-based
assessments
of resources,
checkup events,
distribution of
mass media and
educational print
materials, free and
low-cost booster
seat programs,
booster seat
training in Head
Start preschools
Give Kids a Boost!
Percentage of all
seats inspected that
were boosters
Ability to provide
correct details
regarding nature
and use of booster
seats
Awareness of what
a booster seat is
Percentage of
children aged 4–7
observed riding in
booster seats
32%
Pre
38%
Pre
26%
39%
Post
44%
Post
53%
Pre
5.6%
Post
11%
Proportion of booster seats being
inspected increased after passage of
law
Booster
seat
inspections
57% of parents of children aged 4–9
were unaware of the requirement
that their children should use booster
seats
Russian-speaking parents knew less
about booster seat use than other
parents
Providing
correct
details
Awareness
Observed
booster
seat use
(p=0.025)
48
49
To assess
the impact
of a media
campaign on
use of child
restraints in
Montreal
To assess the
impact of the
1983 Illinois
child restraint
law
To increase use
of child safety
seats among
children 3–4
years old
Rock, 1996
(USA)
Sheese, 1998
(USA)
To determine
differences in
attitudes and
behaviors in
the different
intervention
groups
To determine
the feasibility
of three
school-based
interventions
To test the
effectiveness
of three
school-based
booster seat
intervention
methods
to increase
booster seat
use in a public
school system
Pless et
al., 1986
(Canada)
Philbrook
et al., 2005
(USA)
Pretest/posttest
(before
and after
campaign);
survey;
observation
Pretest/
posttest; ARIMA
techniques
(autoregressive
integrated
moving
average)
Used
observation
Uncontrolled
pretest/posttest
(before and
after campaign)
Used surveys
Uncontrolled
pretest/posttest
Control: None
Target: Children
aged 3–4 in
Indiana
Control: None
Target: Children
aged 0–9
Parents with
young children
in four areas of
Montreal
Children in
kindergarten
in three public
school systems
in Minneapolis,
Minnesota, and
their parents
Statewide media
campaign aimed
at parents
and children;
included visits
to kindergarten
classes
Enactment of law
requiring children
under age 4 to
ride in approved
safety seat and
children aged 4–5
to ride in safety
seat or use seat
belt
Follow-up done
6 months after
baseline
Media campaign
aimed at parents
in English
and French.
Discussions of
campaign on
television and
radio shows,
pamphlets and
posters placed
in health settings
and retail stores
Follow-up done
3 and 6 months
after intervention
All parents who
participated
in evaluation
received free
booster seat
Group 3:
kindergarten
presentation on
booster seat use
and literature sent
home to parents
Group 2: parent
classes (in
Spanish and
English), videos,
free booster seats
Group 1:
information on
booster seats for
parents sent home
with children
Three schoolbased intervention
groups:
Percentage of
children aged 3–4
observed using any
child restraint
Fatalities and
injuries among
children aged 0–9
Percent of children
aged 0–12 years
seen properly
restrained
Booster seat use
Pre
50%
16%
30%
Post
42%
39%
55%
Pre
7.2%
Post
8.6%
Any child
restraint
Pre
25%
Post
41%
Age 5–9: No significant reductions
Aged 0–4: Law resulted in 10%
decrease in number killed or injured,
17% decrease in rate injured per
accident, and 14% decrease in
percentage of all fatalities and injuries
Greater increases seen at sites
with higher proportions of Englishspeakers
Increases were not significant for
children aged 5–11 years
Age 5–11
Solely sending information home to
parents was not an effective means of
increasing booster seat use
Increase for Group 3 was significant
(p=0.025)
Increase for Group 2 was significant
(p=0.011)
Group 1
Group 2
Group 3
Booster seat use:
Limitations
or more social problems. It is noteworthy that most of the Head Start families
in the Johnston et al. study did not have cars with rear-seat lap and shoulder
belts suitable for booster seats; this problem very likely exists in many parts of
the world.
Although the five studies included in our meta-analysis had sufficiently rigorous
designs, two were based on observations and three on self-reports. Self-reports
generally constitute weak evidence, especially in the case of a socially desirable behavior. Since the ultimate objective of these interventions is to increase
actual use of booster seats, it is actual use that should be measured. Although
collecting observational data on restraint use is imperfect and resource intensive
The results of our meta-analysis must be interpreted in the context of a number
(Decina and Lococo 2005), it is the most reliable available means of ascertaining
of limitations. Our review involved extensive searches of numerous databases
actual use. The self-report data in our review was enhanced by corroboration of
as well as contacts with public health and transport safety agencies and experts
booster seat availability, but availability cannot be equated with use.
around the world. The literature search was not restricted by language or by
whether a report had been published. Nevertheless, the five eligible studies we
Some of the included studies suffered from considerable attrition, and, as noted
identified were from developed countries—the United States and Australia—and
earlier, no comparative analyses were conducted to ascertain whether partici-
we found no indication of eligible studies from other countries. Hence, our find-
pants who dropped out differed from those who did not. The study duration and
ings may not be generalizable to all parts of the world. Moreover, it is doubtful
follow-up interval varied greatly as well. For example, there is a marked differ-
that the populations involved in the included studies are even representative
ence between the experimental day care intervention of 2 weeks’ duration in the
of the general populations of the United States and Australia. For example, the
Bowman et al. study and the large multi-intervention community-based trial of 15
middle-class Seattle area communities in the Ebel et al. study seem quite dif-
months’ duration in the Ebel et al. study. Finally, although in our meta-analysis
ferent from the Head Start population studied by Johnston et al. Even within the
the five studies were weighted according to number of cases, the strength of
Ebel et al. study, the per capita income of the study populations (four interven-
the evidence in the studies varies.
tion communities and eight control communities) ranged from $15,260 (with 20
percent living in poverty) to $53,800 (with 3 percent living in poverty).
Notwithstanding these limitations, this review has clear implications for future
research and practice aimed at increasing booster seat use for 4–8-year-olds.
Given the resources needed to conduct interventions such as those implemented by Johnston et al. and O’Neil et al., replication would not be feasible in
many countries. Similarly, the level of community involvement in the Ebel et al.
study might be difficult to achieve in poor countries that have fewer resources
50
51
Conclusion
bilization and participation, is more effective than an incentives-only approach.
We do not know how incentives-only programs compare with either distributiononly or education-only interventions, nor do we know what effect community
mobilization and participation have on intervention effectiveness.
Investigations of what works best in different populations and settings (e.g., affluent and poor neighborhoods) are also important, since there may be differences
between the behaviors of low-income parents and those of the more affluent,
or between urban and rural parents. Ascertainment of any such differences is
important to ensure proper targeting of future interventions.
IMPLICATIONS FOR RESEARCH
Other important areas for future research include cost-effectiveness analyses
and studies of interventions in high-risk populations. We acknowledge the practi-
Despite our broad and exhaustive search, only five studies of good to excellent
cal challenges of collecting observational data, including the time required, the
quality were found on interventions to increase use of booster seats. Given the
cost, and reliability issues. However, actual use of booster seats in the real world
dearth of available high-quality evaluation studies, future efforts to increase
is a stronger measure of intervention effectiveness than self-reported use or
booster seat use should be accompanied by rigorous assessments of their
ascertaining whether someone purchased a booster seat. Longer-term studies
effectiveness, using well-designed approaches to minimize bias and ensure
with larger populations should be implemented to clarify the long-term impacts
the validity and reliability of the results. Randomized controlled trials as well as
of various interventions in different populations.
prospective controlled trials are needed, especially with community-based inter-
52
ventions that are replicable and sustainable under normal field conditions.
IMPLICATIONS FOR PRACTICE
A useful focus for future research would be a demonstration of the individual
The development of strategies for increasing the acquisition and use of booster
effects of the different types of interventions (education, incentives, distribution,
seats by families with young children is an evolving project. The results of this
legislation/enforcement). None of the studies included in our review compared,
review suggest that multiple-intervention approaches can be used effectively
for example, distribution of booster seats alone versus no distribution (i.e., with-
to increase booster seat acquisition and use. Strategies using incentives and
out education included in the intervention) or law enforcement alone versus no
education, distribution and education, and education-only interventions produced
enforcement.
varying effects.
It would be particularly useful to know whether a multiple-intervention strategy
Interventions based in part on incentives or distribution of free booster seats
such as the one used by Ebel et al., which involved significant community mo-
require funding and may not be feasible in all communities. Although some
53
socially oriented governments or local health departments might fund booster
seat distribution or discount coupons, very few governments or local councils in
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Appendices
APPENDIX 1:
SEARCH STRATEGY FOR IDENTIFICATION OF STUDIES
MEDLINE (1966–April 2005)
1.
“Infant-Equipment” / all SUBHEADINGS
2.
child seat* or infant seat* or (child near restraint*)
3.
“Seat-Belts” / all SUBHEADINGS or “Protective-Devices” / all
SUBHEADINGS
4.
booster seat* or safety seat* or car seat* or (vehicle near restrain*) or
(car near restrain*) or (automobile near restrain*) or (automotive near
restrain*)
5.
#1 or #2
6.
#3 or #4
7.
“Automobiles-” / all SUBHEADINGS
8.
motor vehicle* or car or cars or automobile*
9.
#7 or #8
10. explode “Child-” / all SUBHEADINGS
11. child* or infant*
12. #10 or #11
13. #9 and #5
14. #12 and #9 and #6
15. #13 or #14
64
65
16. promot* or train* or educat* or counsel* or legislat*
Web of Science (WoS) (April 2005)
17. #16 and #15
1.
(booster seat* OR safety seat*) AND (promot* OR train* OR educat* OR
counsel* OR legislat*)
EMBASE (1980–April 2005)
2.
(car seat* OR vehicle restrain* OR car restrain* OR automobile restrain*
1.
*Protective Equipment/
OR automotive restrain*) AND (child* OR infant*) AND (promot* OR train*
2.
((child adj seat$) or (infant adj seat$) or (child adj3 restrain$)).ti,ab.
OR educat* OR counsel* OR legislat*)
3.
1 or 2
4.
exp SEATBELT/
automobile* OR motor vehicle*) AND (promot* OR train* OR educat* OR
5.
((booster adj seat$) or (safety adj seat$) or (car adj seat$) or (vehicle adj3
counsel* OR legislat*)
restrain$) or (car adj3 restrain$) or (automobile adj3 restrain$) or (automo-
3.
4.
(child seat* OR infant seat* OR child restraint*) AND (car OR cars OR
#1 OR #2 OR #3
tive adj3 restrain$)).ti,ab.
6.
4 or 5
7.
exp CAR/
8.
((motor adj vehicle$) or car or cars or automobile$).ti,ab.
9.
7 or 8
ERIC (no dates; all years up to April 2005)
1.
booster seat* or safety seat* or car seat* or vehicle restrain* or car restrain*
or automobile restrain* or automotive restrain* or child seat* or infant seat*
or child restrain*
10. Child/
11. (child$ or infant$).ti,ab.
12. 10 or 11
TRANSPORT (1988–April 2005) / ATI (1976–April 2005)
13. 3 and 9
14. 6 and 12
1.
CHILD-RESTRAINT-SYSTEMS
15. 13 or 14
2.
CHILD-RESTRAINT-SYSTEMS-IN-AUTOMOBILES
16. Clinical Trial/
3.
BOOSTER-SEATS
17. Controlled Study/
4.
#1 or #2 or #3
18. (randomi$ or (controlled adj trial$) or (double adj blind$) or (single adj blind$)
5.
seat?belt*
6.
child seat* or infant seat* or child restrain* or #5
19. Review/
7.
car or cars or automobile* or (motor adj vehicle*)
20. 16 or 17 or 18 or 19
8.
#6 and #7
21. 15 and 20
9.
booster seat* or safety seat* or car seat* or (vehicle adj restrain*) or (auto-
or (clin$ adj3 trial$) or placebo$ or review$).ti,ab.
22. 21
23. limit 22 to human
66
mobile adj restrain*) or (automotive adj restrain*)
10. (child* or infant*)
67
1.
68
National Safety Council
1.
booster! – keyword
2.
child seats ! booster* AND restraint* & (education / program* / information
/ campaign*)
Society of Automotive Engineers (SAE)
booster* & child*
Cluster
randomized
control trial
at child care
centers to
increase
possession and
use of booster
seats
Controlled
prospective
community trial
to increase
booster seat use
among Latino
families
Colorado
Department
of Public
Health and
Environment
Ebel
Latino families
in urban
and rural
communities
Parents of
children
attending child
care centers
• Development and
dissemination of
culturally tailored
intervention materials
based on extensive
qualitative research
• Incorporation of
behavior change
messages into
radionovelas, television
public service
announcements,
posters, and brochures
• Critical involvement
of Latino advisory
councils
• Partnerships
with community
organizations
developing
culturally specific
law enforcement
partnerships
Education, distribution,
incentive
Education, distribution
d. NKHL – Effectiveness
Parents of Tball participants
Changes in
observed
booster seat
use
Increase in
booster seat
use
Increase in
booster seat
use
c. QD Training
Strike Out Child
Passenger
Injury
2004
October
2003
Spring
2005
Beth Ebel
([email protected])
Sallie Thoreson
(sallie.thoreson@state.
co.us)
Mary Aitken
([email protected])
Contact
UMTRI
Aitken
b. YCO – Campaigns
Start
Date
In subject headings: DGEORF & (YCO/RCCEC/YCO/QD) & NHKL:
Outcomes
Booster* & Child*
Intervention
Expected to
be completed
in 2006
Expected to
be completed
in 2007
Remarks
14. #12 and #13
Participants
13. promot* or train* or educat* or counsel* or legislat*
Title or
Description
12. #4 or ##8 or #11
Study ID
1.
APPENDIX 2: CHARACTERISTICS OF ONGOING STUDIES
11. #9 and #10
a. DGEORF – Child Restraints / Child Seats
69
70
71
Prospective
community
intervention to
increase booster
seat use in
high-risk urban
populations,
using a
communitybased program;
component of
the Injury-Free
Coalition for
Kids program
An independent
evaluation of
the ThinkFirst
Foundation
for Injury
Prevention’s
“Boost’ em Up”
program
Statewide
survey of
booster seat use
“Think First”
Four-Site
Demonstration
Project
Johnston
Kostyniuk
Nebraska
Department
of Motor
Vehicles
National
Highway
Traffic
Safety
Administration
Parents of
children in the
booster seat
age range
Parents of
children in the
booster seat
age range
Children 4–8
years old and
their families
Families
in urban
communities
at high risk of
occupant injury
Education
Legislation, education,
distribution
A variety of
interventions to
increase booster seat
use at the local level
• Development and
dissemination of lowliteracy, multilanguage
materials
• Capacity building to
increase booster seat
availability at urban
retail outlets
• Outreach education
to ethnically diverse
Head Start programs,
churches, community
service providers
• Low-cost booster
seat sales in targeted
communities
Increase in
booster seat
use
Increase in
booster seat
use
Observed
booster seat
use and
impact of
the various
interventions
on the
incidence
of child
crash-related
injuries
Changes in
observed
booster seat
use
September
2003
2004
2004
2004
Alexander Sinclair
([email protected].
gov)
Cathy Chochon
([email protected].
ne.us)
Lidia Kostyniuk
([email protected])
Brian Johnston
([email protected])
Will conclude
in 2006
Not
necessarily
an
intervention.
Will conclude
in 2005
Will conclude
in 2007
Expected to
be completed
in 2006
72