Child Restraint System Misuse Research Articles

Child safety in cars: An observational study on the use of child restraint systems in The Netherlands

Objective To minimize children’s injuries due to car accidents, children must be transported in approved child restraint systems (CRS). The European Union optimized child protection by implementing R129 legislation for CRS in 2013. However, compliance with CRS recommendations after introduction of this newer standard has been scarcely evaluated. The main objectives of this study were to determine the prevalence of various types of CRS misuse and to investigate the use of ISOFIX and i-Size seats and parental knowledge regarding safe transportation of children in cars 5 years after the introduction of the newer R129 standard. Methods During a cross-sectional observational study in the summer of 2018, parking lots of sites in the Netherlands were visited by researchers. Arriving or departing Dutch drivers who transported children under 9 years old were interviewed by means of a questionnaire and the misuse of CRS was directly observed using a checklist. Misuse was defined as CRS inappropriate for the child (based on height and weight) and/or CRS wrongly installed in the car and/or child improperly restrained in CRS. Results In total, 392 drivers and 470 children were included in the study. Results showed that 83% of the children were transported with at least 1 misuse of their CRS: 7% of the CRS were inappropriate for the child, 49% of the CRS were wrongly installed in the car, and 59% of the children were improperly restrained in a CRS. Most CRS were installed using the seat belt (88%) compared to ISOFIX (12%). ISOFIX usage did not result in less CRS installation misuse (P = .338). The number of observed i-Size CRS was low (n = 13, 3%). Most drivers were familiar with ISOFIX (76%), but only 13% of the drivers had heard of i-Size. Conclusions For 9 out of 10 children, CRS misuse was observed. Many children were transported in an appropriate CRS, but various mistakes were made when installing the CRS in the car and restraining children in the CRS. Moreover, ISOFIX usage did not result in statistically significant less CRS installation misuse compared to traditional seat belt usage, and i-Size CRS are still rather unknown 5 years after their introduction.

A Study on the Use and Misuse of Child Restraint System (CRS) in Malaysia


 
 
 In car crashes, children are more likely to suffer more severe injuries than adults. For prevention, Child Restraint System (CRS) is normally used. However, inappropriate use of CRS may exacerbate injury risks. This research aims to determine the prevalence of CRS use and misuse among car owners, especially those travelling with children aged 11 years and below. A total of 178 parents were interviewed and 267 children were observed. Overall, only 12.7% children were properly restrained in CRS for their size, with the correct installation and appropriate seating position. Prior to CRS law implementation, initiatives such as awareness campaigns, community based programs and CRS clinics should be introduced.
 
 

Effects of child restraint misuse on dynamic performance

Objective: Estimates of child restraint misuse rates in the United States range from 49% to 95%, but not all misuse modes have similar consequences in terms of restraint effectiveness. A series of laboratory sled tests was conducted to determine the effects of common misuses and combinations of misuses, including loose harness, loose installation, incorrect installation angle, incorrect belt path, loose/no tether, and incorrect harness clip usage.Methods: Three commercial convertible child restraint models were loaded with the Hybrid III 3-year-old anthropomorphic test device (ATD) and secured by either LATCH or seat belt on a modified FMVSS No. 213 bench. Tests were conducted in forward-facing (FF) and rear-facing (RF) modes. The response variables included ATD accelerations, excursions, and restraint kinematics. Belt/LATCH loads, tether loads, ATD kinematics, and restraint structural response data were also documented. A fractional factorial test design on 8 factors was used to define an initial series of 32 tests. The first series also included 4 tests of correct CRS, 2 forward facing and 2 rearward facing. The analysis of those data determined the selection of conditions for the remaining 20 tests to focus on factors and interactions of high interest and significance.Results: In the RF condition, misrouting the LATCH belt or seat belt through the incorrect belt path was the only misuse that significantly affected outcomes of interest and was associated with high levels of undesirable CRS rotation. In FF tests, loose installation and tether misuse had large adverse effects on 3 of 4 key response variables.Conclusion: The study provides strong evidence for prioritizing tight restraint installation and proper tether use for FF restraints. In particular, use of the tether helped offset the adverse effects of loose installation or loose harness. Because the results show that performance of a RF child restraint system (CRS) installation is less affected by user error, they also provide support for extended RF restraint use. In addition, packaging convertible child restraints with the LATCH belt routed through the RF belt path could help prevent the most consequential RF CRS misuse.

Standardized error severity score (ESS) ratings to quantify risk associated with child restraint system (CRS) and booster seat misuse

ABSTRACTObjective: Although numerous research studies have reported high levels of error and misuse of child restraint systems (CRS) and booster seats in experimental and real-world scenarios, conclusions are limited because they provide little information regarding which installation issues pose the highest risk and thus should be targeted for change. Beneficial to legislating bodies and researchers alike would be a standardized, globally relevant assessment of the potential injury risk associated with more common forms of CRS and booster seat misuse, which could be applied with observed error frequency—for example, in car seat clinics or during prototype user testing—to better identify and characterize the installation issues of greatest risk to safety.Methods: A group of 8 leading world experts in CRS and injury biomechanics, who were members of an international child safety project, estimated the potential injury severity associated with common forms of CRS and booster seat misuse. These injury risk error severity score (ESS) ratings were compiled and compared to scores from previous research that had used a similar procedure but with fewer respondents. To illustrate their application, and as part of a larger study examining CRS and booster seat labeling requirements, the new standardized ESS ratings were applied to objective installation performance data from 26 adult participants who installed a convertible (rear- vs. forward-facing) CRS and booster seat in a vehicle, and a child test dummy in the CRS and booster seat, using labels that only just met minimal regulatory requirements. The outcome measure, the risk priority number (RPN), represented the composite scores of injury risk and observed installation error frequency.Results: Variability within the sample of ESS ratings in the present study was smaller than that generated in previous studies, indicating better agreement among experts on what constituted injury risk. Application of the new standardized ESS ratings to installation performance data revealed several areas of misuse of the CRS/booster seat associated with high potential injury risk.Conclusions: Collectively, findings indicate that standardized ESS ratings are useful for estimating injury risk potential associated with real-world CRS and booster seat installation errors.

A novel method for quanitifying comfort in child passengers demonstrates an association between child restraint comfort and errors in use of booster seats

ABSTRACTObjective: Misuse of child restraint systems is a widespread and long-standing problem impacting risk of injury and death in car crashes. Discomfort has been suggested as a causative factor for misuse, particularly in errors introduced by children while they use the restraints. However, the relationship between comfort and errors in use has never been studied. In this study we examine the reliability and sensitivity of a newly developed observational method for assessing comfort in children in vehicles. We then use this method to examine the relationship between comfort and errors in use of booster seats.Methods: A novel method was developed for assessing comfort by counting fidgeting and postural adjustment behaviors to derive a Discomfort Avoidance Behavior (DAB) score. The sensitivity of the DAB score was examined by observing children in four different seating conditions designed as “comfortable” and “uncomfortable” (Part 1). Paired-samples t-tests were used to compare differences in DAB between seating conditions. The reliability of the DAB score was assessed by calculating the intraclass correlation coefficient (ICC) between DAB scores recorded by different researchers. The association between comfort and correctness of use was examined by observing children using booster seats (Part 2). The association between DAB score and number of usage errors was tested using linear regression analysis. Participants were children ages 4–8 years. Fourteen children participated in Part 1 and 15 children in Part 2.Results: The DAB score was sensitive to changes in seat condition (p < 0.01), and was repeatable between different researchers (ICC 0.98, 95% confidence interval [CI] 0.954–0.991). Increases in DAB were associated with increases in the number of use errors among children using booster seats (errors in use = 3.89 × DAB − 2.18, p < 0.0001).Conclusion: The DAB score is a reliable and valid measure of comfort of children in child restraints but could be improved by incorporating a measurement of postural positioning. Comfort, as characterized by fidgeting and postural adjustment behaviors, is associated with correct use of child restraints. The broader implication is that this confirms ergonomic design of child restraints as important for minimizing errors in use. There is a need for further study of the impact of specific restraint design features on comfort experienced by children.

Investigation of Child Restraint System (CRS) Compatibility in the Vehicle Seat Environment

Objective: Child restraint system (CRS) misuse is common and can have serious consequences to child safety. Physical incompatibilities between CRS and vehicles can complicate the installation process and may worsen CRS misuse rates. This study aims to identify the most common sources of incompatibility between representative groups of CRS and vehicles.Methods: Detailed dimensional data were collected from 59 currently marketed CRS and 61 late model vehicles. Key dimensions were compared across all 3,599 theoretical CRS/vehicle combinations and the most common predicted incompatibilities were determined. A subset of 34 physical installations was analyzed to validate the results.Results: Only 58.2% of rear-facing (RF) CRS/vehicle combinations were predicted to have proper agreement between the vehicle's seat pan angle and the CRS manufacturers’ required base angle. The width of the base of the CRS was predicted to fit snugly between the vehicle's seat pan bolsters in 63.3% of RF CRS/vehicle combinations and 62.2% of forward-facing (FF) CRS/vehicle combinations. FF CRS were predicted to be free of interaction with the vehicle's head restraint in 66.4% of combinations. Roughly 90.0% of RF CRS/vehicle combinations were predicted to have enough horizontal clearance space to set the front seat in the middle its fore/aft slider track. Compatibility rates were above 98% regarding the length of the CRS base compared to the length of the vehicle seat pan and the ability of the top tether to reach the tether anchor. Validation studies revealed that the predictions of RF CRS base angle range vs. seat pan angle compatibility were accurate within 6%, and head restraint interference and front row clearance incompatibilities may be more common than the dimensional analysis approach has predicted.Conclusions: The results of this study indicate that RF CRS base angles and front row clearance space, as well as FF CRS head restraint interference, are frequent compatibility concerns. These results enable manufacturers, researchers, and consumers to focus their attention on the most relevant CRS/vehicle incompatibility issues in today's market.

The Impact of New Legislation on Child Restraint System (CRS) Misuse and Inappropriate Use in Australia

Objective: The current study aimed to investigate the incidence of child restraint system (CRS) misuse and/or inappropriate use of CRS through an Australian CRS inspection program conducted by CRS fitting specialists between October 2004 and October 2011 and to determine whether CRS misuse and/or inappropriate use of CRS changed following new Australian legislation regarding CRS and motor vehicle restraint use for children aged 7 years and under. Methods: Participants were recruited through an advertisement for free CRS inspections displayed at childcare centers, kindergartens, community centers, hospitals, and child expos. At each inspection, a CRS fitting specialist inspected each child in their CRS while in their vehicle and reported to the owner of the CRS on the installation of the child restraint(s) and/or system(s) and any fitting faults and/or concerns with the fitting and/or use of the child restraint(s) and or system(s). Results: Results are based on the inspection of 2674 CRS. Of all of the CRS inspected, the majority (79%) were reported as having at least one instance of misuse and/or inappropriate use. The most common forms of CRS misuse and/or inappropriate use observed were harness strap errors (twisted, poorly adjusted, and/or incorrectly positioned, 41%), seat belt errors (incorrectly routed, twisted, and/or incorrectly adjusted, 32%), and a missing or incorrect fitting of the gated buckle/locking clip (24%). Significant differences were found across the proportion of CRS misuse and/or inappropriate use across restraint types (infant restraint/forward-facing CRS/convertible [birth to 18 kg] CRS/convertible [8–26 kg] CRS/boosters [booster seat/cushion/booster with harness combination]), χ2(4) = 147.852, P < .001. CRS misuse and/or inappropriate use were most prevalent among convertible CRS (birth to 18 kg; 87%), forward-facing CRS (85%), and convertible CRS (8–26 kg; 81%), compared to infant restraints (73%) and booster seats (booster seats/cushions/boosters with H-harness combination; 65%). There was no significant difference in the proportion of CRS with misuse and/or inappropriate use across the pre- and post-legislation period (80% vs. 77%), χ2(1) = 1.545, P > .5. Conclusions: Based on the findings of the current study, it was concluded that, despite the introduction of new, definitive CRS legislation, CRS misuse and/or inappropriate use remains widespread in Australia. The findings highlight the need for CRS education and legislation that include information on correct CRS use, as well as information on appropriate CRS use, in order to provide specialized protection for child vehicle occupants in the event of a motor vehicle crash.

Child Restraint System Misuse and/or Inappropriate Use in Australia

Objective: Motor vehicle crashes are one of the leading causes of child death and acquired disability. Child restraint systems (CRS) for vehicles are designed to provide specialized protection for child occupants in the event of a crash. However, the effectiveness of a CRS is critically dependent on: correct installation of the CRS in the vehicle, the correct harnessing of the child in the CRS, and use of an appropriate CRS. The current study aimed to investigate the incidence misuse and/or inappropriate use of CRS through a CRS inspection program in the Australian states of New South Wales (NSW), Victoria (VIC), Queensland (QLD), South Australia (SA), Western Australia (WA), and Tasmania (TAS). Methods: Participants were recruited through an advertisement for free CRS inspections displayed at childcare centers, kindergartens, community centers, hospitals, and child expos. At each inspection, the CRS fitting specialist inspected and reported to the owner of the CRS on the installation of the child restraint(s) and/or system(s) and any fitting faults and/or concerns with the fitting and/or use if the child restraint(s) and or system(s). Results: The following results are based on the inspection of 1386 vehicles, in which there were 1995 restraints. Of all the restraints inspected, the majority (79%) were reported as having at least one instance of misuse. The most common forms of misuse included harness strap errors such as the straps being adjusted, faulty, twisted, and/or incorrectly positioned (38%); seat belt errors such as the seatbelt being incorrectly routed, twisted, and/or incorrectly adjusted (32%); missing or incorrect fitting of gated buckle/locking clip (23%); the need for a missing sash guide (8%); tether errors such as the tether being incorrectly routed and/or adjusted (7%); inappropriate use of a CRS for the size of the child (6%); anchor errors such as the anchor was fitted incorrectly or not the correct type (5%); and the H Harness1 being used incorrectly (5%). In addition, there were significant differences across restraint types in terms of the proportion of restraints with CRS misuse or fitment errors, χ2 (2) = 51.42, p < 0.001. The rate of misuse was highest for the forward-facing CRS (88%), compared to infant seats (67%) and booster seats or cushions (63%). 1 An H harness is an additional device that is designed for use with or without booster seats for children weighing up to 32 kg. The harness is attached to the vehicle at the same point as a CRS top tether, with the lap belt of the vehicle threaded through the harness. Discussion: The results show that CRS misuse and fitment errors are widespread in Australia. Based on the findings of this study, it is recommended that educational and awareness materials and programs that provide information on the safety benefits associated with correct CRS use (as well as the injury risk associated with CRS misuse) be developed for both parents and children.

Premature graduation of children in child restraint systems: An observational study

This study investigated the use and misuse of child restraint systems (CRS) in Flanders (Belgium). Observations were conducted at a random sample of primary school and recreation areas. In total 1376 children were observed. A logistic regression model was constructed in order to determine the variables involved. The parameter-estimates of this model have shown that children are more often restrained when the driver buckles up, the ride takes less than 1 h, the children are younger, the children sit in the front seat of the car, a recreational area is the destination of the trip and there are less than five children in the car. Also premature graduation to CRS was analysed. More than half of the children are not appropriately restrained, according to their age, weight or height. Improper shoulder belt use (putting the shoulder belt behind the back or under the arm) was observed in 8.99% of the children being restrained with high back booster seats, in 32.73% of the children being restrained with backless booster seats and finally in 19.07% of the children being restrained with seat belts. The risk of incorrectly using the shoulder belt increases when children are prematurely graduated in a CRS. The results are discussed in the light of other studies on this matter.

Child restraint system use and misuse in six states

This project addressed use and misuse of child restraint systems (CRS) in the nation. CRS use and critical misuse observations were collected in the Fall of 2002 for 5527 children less than 36 kg (80 pounds) in 4126 vehicles in six states: Arizona, Florida, Mississippi, Missouri, Pennsylvania, and Washington. Results showed that 62.3% of these children were restrained in a CRS; 25.9% were restrained in a safety belt (SB); and 11.8% were unrestrained. By weight class, CRS use was 97.1% for children less than 9 kg (20 pounds); 86.4% for children between 9 and 18 kg (20 and 40 pounds); 41.7% for children between 18 and 27 kg (40 and 60 pounds); and 10.9% for children between 27 and 36 kg (60 and 80 pounds). Overall critical CRS misuse was 72.6%. Most common critical misuses were loose harness straps and loose vehicle SB attachment to the CRS. Other types of CRS misuses were also observed and recorded in the study. Recommendations are provided for field observation techniques, periodic monitoring, and research for education and enforcement strategies.

The Effect of Misuse of Child Restraint Systems in Accidents

Although child restraint systems (CRS) have improved the transportation of young children, approximately 85 percent of CRS are improperly used (National Safe Kids, 1999). This accident-based study was conducted to examine how CRS and seat belts are misused, what is the effect of that misuse, and how caregivers learn about proper usage of CRS. Data from 194 children involved in accidents showed that more than two-thirds were not in the appropriate restraint for their age, height, and weight; over half were improperly restrained in a CRS; and about one-quarter used seatbelts improperly. Over half of the caregivers who read the CRS manual used the CRS improperly. The data also show that regardless of whether the restraint was used properly or improperly, most of the children sustained no or minor injuries. Measures to improve child restraint and seatbelt use include educational outreach, improvements in CRS and automobile design and State legislative initiatives.

Assessing child restraint misuse by parental survey

Objective—To determine the extent to which child restraint system (CRS) misuse can be evaluated by parental survey. Methods—A cross sectional survey was conducted at eight CRS clinics from May to...

Misuse mode and effects analysis—An approach to predict and quantify misuse of child restraint systems

It is known that misuse of Child Restraint Systems (CRS) is widespread and must be considered as a major threat to the safety of children. In this paper a quantitative method of predicting and assessing misuse of CRS is proposed. The process, called “Misuse Mode and Effects Analysis (MMEA)” assesses the likelihood of occurrence of potential misuse modes and their effect on safety before and after corrective actions. The effectiveness of the proposed method is demonstrated in the assessment of a number of commonly used CRS.