Motor Vehicle Injury Child Safety Seats: Laws Mandating Use

Summary of CPSTF Finding

The Community Preventive Services Task Force (CPSTF) recommends child safety seat laws to increase their use.

Intervention

Child safety seat laws require children use federally approved infant or child safety seats when riding in a motor vehicle. Requirements vary by state based on a child’s age, weight, and height. Enforcement guidelines and penalties also vary, though law enforcement in all states can stop drivers if child passengers are not properly restrained.

CPSTF Finding and Rationale Statement

Read the CPSTF finding.

About The Systematic Review

The CPSTF finding is based on evidence from a systematic review of nine studies (search period through March 1998).

The review was conducted on behalf of the CPSTF by scientists from CDC’s Division of Unintentional Injury Prevention with input from a team of specialists in systematic review methods and experts in research, practice, and policy related to motor vehicle injury prevention.

Context

All 50 states, the District of Columbia, Guam, the Northern Mariana Islands, and the Virgin Islands have child safety seat laws in place. Each law specifies the children they cover in terms of age, height, weight, or a combination of these factors.

Summary of Results

More details about study results are available in the published evidence review.

The systematic review included nine studies.

  • Fatal injuries decreased by a median of 35% (3 studies)
  • Fatal and nonfatal injuries combined decreased by a median of 17% (5 studies)
  • Observed child safety seat use increased by a median of 13 percentage points (3 studies)
  • Among the studies that evaluated the laws’ effects on injury rates, researchers found no differences in the effect size based on the age of children who were required to be in safety seats.

Summary of Economic Evidence

An economic review of this intervention did not find any relevant studies.

Applicability

The results of these studies should be applicable to most child passengers in the United States. More specific information on applicability is not available because none of the studies looked at age, sex, race, socioeconomic status, or regional differences within states.

Evidence Gaps

CPSTF identified several areas that have limited information. Additional research and evaluation could help answer the following questions and fill remaining gaps in the evidence base. (What are evidence gaps?)
  • Does the effectiveness of child safety seat laws vary depending on the requirements of different state laws?
  • Does effectiveness of laws vary depending on the intensity and visibility of regular enforcement in the state?
  • Would the threat of being charged with contributory negligence if an unrestrained child is killed or injured in a motor vehicle crash change the effectiveness of the law?
  • What role does information about laws play in compliance rates?
  • How can the effectiveness of a child safety seat law be maintained over time?
  • Is the intervention likely to increase or reduce misuse of child safety seats?
  • Are child passenger safety laws equally effective in all populations (e.g., racial and ethnic minorities, high- and low-income populations, or behavior change-resistant populations)?
  • Are laws effective in populations that already have high baseline safety seat use rates?
  • What are intervention costs?
  • Are child passenger safety laws cost-saving?
  • What is the return on investment for these interventions?

Study Characteristics

  • Laws evaluated in the included studies reported the following characteristics:
    • Primary enforcement. All laws allowed for primary enforcement, that is, a driver could be stopped for the sole purpose of being cited and fined for failure to comply with the child safety seat law.
    • Age requirements. The laws applied to children of various ages (e.g., some applied to children up to the age of 1 year, whereas others applied to children up to the age of 5 years).
    • Seating position. One study specified that the law applied only to children in the front seat; the remainder of the studies did not specify seating requirements.
    • Penalties. The various laws allowed for penalties, ranging from an oral warning to a $25 fine.
  • Studies evaluated the effectiveness of child safety seat laws enacted between 1978 and 1986 in all 50 states.
  • None of the studies examined other activities related to child safety seat laws, such as programs to lend seats to low-income families, levels of enforcement, or publicity about the law.

Publications

Zaza S, Sleet DA, Thompson RS, Sosin DM, Bolen JC, Task Force on Community Services. Reviews of evidence regarding interventions to increase use of child safety seats. American Journal of Preventive Medicine. 2001;21(4S):31-47.

Task Force on Community Services. Recommendations to reduce injuries to motor vehicle occupants: increasing child safety seat use, increasing safety belt use, and reducing alcohol-impaired driving. American Journal of Preventive Medicine. 2001;21(4S):16-22.

Zaza S, Carande-Kulis VG, Sleet DA, et al. Methods for conducting systematic reviews of the evidence of effectiveness and economic efficiency of interventions to reduce injuries to motor vehicle occupants. American Journal of Preventive Medicine. 2001;21(4S):23-30.

Centers for Disease Control and Prevention. Motor-vehicle occupant injury: strategies for increasing use of child safety seats, increasing use of safety belts, and reducing alcohol-impaired driving. MMWR. 2001;50(RR-7):1-13. Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5007a1.htm.

Zaza S, Sleet DA, Elder RW, Shults RA, Dellinger A, Thompson RS. Response to letter to the editor. American Journal of Preventive Medicine. 2002;22:330-1.

Sleet DA. Evidence based injury prevention: guidance for community action. In: Australian Third National Conference on Injury Prevention and Control. Australian Third National Conference on Injury Prevention and Control. Brisbane, Queensland, Australia; 1999.

Miller TR. The effectiveness review trials of Hercules and some economic estimates for the stables. American Journal of Preventive Medicine. 2001;21(4S):9-12.

Webb M. Research as an advocate’s toolkit to reduce motor vehicle occupant deaths and injuries. American Journal of Preventive Medicine. 2001;21(4S):7-8.

Waller PF. Public health’s contribution to motor vehicle injury prevention. American Journal of Preventive Medicine. 2001;21(4S):3-4.

Satcher D. Note from the Surgeon General. American Journal of Preventive Medicine. 2001;21(4S):1-2.

Novick LF, Kelter A. Guide to Community Preventive Services: a public health imperative. American Journal of Preventive Medicine. 2001;21(4S):13-15.

Moffat J. Motor vehicle occupant injury prevention: the states’ perspective. American Journal of Preventive Medicine. 2001;21(4S):5-6.

Task Force on Community Services, Zaza S, Briss PA, Harris KW. Motor vehicle occupant injury. In: The Guide to Community Preventive Services: What Works to Promote Health?. The Guide to Community Preventive Services: What Works to Promote Health? Atlanta (GA): Oxford University Press; 2005:329-84.

Analytic Framework

Effectiveness Review

Analytic Framework see Figure 1 on page 32

When starting an effectiveness review, the systematic review team develops an analytic framework. The analytic framework illustrates how the intervention approach is thought to affect public health. It guides the search for evidence and may be used to summarize the evidence collected. The analytic framework often includes intermediate outcomes, potential effect modifiers, potential harms, and potential additional benefits.

Included Studies

The number of studies and publications do not always correspond (e.g., a publication may include several studies or one study may be explained in several publications).

Effectiveness Review

Evans WN, Graham JD. An estimate of the lifesaving benefit of child restraint use legislation.J Health Econ 1990;9:121 42.

Guerin D, MacKinnon DP. An assessment of the California child passenger restraint requirement. Am J Public Health 1985;75:142 4.

Margolis LH, Wagenaar AC, Liu W. The effects of a mandatory child restraint law on injuries requiring hospitalization. Am J Dis Child 1988; 142:1099 103.

Rock SM. Impact of the Illinois child passenger protection act: a retrospective look. Accid Anal Prev 1996;28:487 92.

Seekins T, Fawcett SB, Cohen SH, et al. Experimental evaluation of public policy: the case of state legislation for child passenger safety. J Appl Behav Anal 1988;21:233 43.

Sewell CM, Hull HF, Fenner J, Graff H, Pine J. Child restraint law effects on motor vehicle accident fatalities and injuries: the New Mexico experience. Pediatrics 1986;78:1079 84.

Wagenaar AC, Maybee RG, Sullivan KP. Michigan’s compulsory restraint use policies: effects on injuries and deaths. Ann Arbor: University of Michigan Transportation Research Institute, 1987. UMTRI 87-10.

Wagenaar AC, Webster DW, Maybee RG. Effects of child restraint laws on traffic fatalities in eleven states. J Trauma 1987;27:726 32.

Williams AF, Wells JK. Evaluation of the Rhode Island child restraint law. Am J Public Health 1981;71:742 3.

Search Strategies

The following outlines the search strategy used for reviews of these interventions to increase use of child safety seats: Laws Mandating Use; Community-Wide Information and Enhanced Enforcement Campaigns; Distribution and Education Programs; Incentive and Education Programs; Education Programs When Used Alone.

The reviews of interventions to reduce motor vehicle-related injury reflect systematic searches of multiple databases as well as reviews of reference lists and consultations with experts in the field. The team searched six computerized databases (MEDLINE, Embase, Psychlit, Sociological Abstracts, EI Compendex, and Transportation Research Information Services [TRIS]), which yielded 10,958 titles and abstracts for articles, book chapters, reports, and published papers from the Association for the Advancement of Automotive Medicine proceedings about safety belts, alcohol-impaired driving or child passenger safety. Studies were eligible for inclusion if:

  • They were published from the originating date of the database through June 2000 (March 1998 for child safety seat interventions)
  • They involved primary studies, not guidelines or reviews
  • They were published in English
  • They were relevant to the interventions selected for review
  • The evaluation included a comparison to an unexposed or less-exposed population
  • The evaluation measured outcomes defined by the analytic framework for the intervention

The search strategy specific to child passenger safety is not available.

Considerations for Implementation

The following considerations are drawn from studies included in the evidence review, the broader literature, and expert opinion.
  • Engage partners throughout the process. Building support from the ground up can help secure policies that reinforce healthy behaviors in the community.
  • Demonstrate why the policy is important. Use CPSTF findings and recent surveillance data to show partners how policies have been effective, and explain how strengthening them could further improve health outcomes in their community.
  • Educate stakeholders. Keep the media, community influencers, and policymakers informed about child passenger safety to help communicate messages that are accurate and timely.
    • Keep messages brief and to the point. Use graphics, figures, or infographics to clearly demonstrate how the intervention can improve health outcomes.
    • Extend your communication reach by working through partners who have the most credibility with key audiences.
  • Pay attention to sustainability. Continue to monitor child passenger safety seat use and share findings.