Global diffusion of three road safety policies, 1964–2015

Global convergence of public policies has been regarded as a defining feature of the late twentieth century. This study explores the generalizability of this thesis for three road safety measures: (i) road safety agencies; (ii) child restraint laws; and (iii) mandatory use of daytime running lights. This study analyzes cross-national longitudinal data using survival analysis for the years 1964–2015 in 181 countries. The first main finding is that only child restraint laws have globally converged; in contrast, the other two policies exhibit a fractured global convergence process, likely as the result of competing international and national forces. This finding may reflect the lack of necessary conditions, at the regional and national levels, required to accelerate the spread of policies globally, adding further nuance to the global convergence thesis. A second finding is that mechanisms of policy adoption, such as imitation/learning and competition, rather than coercion, explain more consistently global and regional convergence outcomes in the road safety realm. This finding reinforces the idea of specific elective affinities, when explaining why the diffusion of policies may or not result in convergence. Lastly, by recognizing fractured convergence processes, these results call for revisiting the global convergence thesis and reintegrating more consistently regional analyses into policy diffusion and convergence studies.

Child restraint use in motor vehicles in Shanghai, China: a multiround cross-sectional observational study

ObjectivesWhile appropriate child restraint use in motor vehicles can reduce the risk of injuries or deaths, few previous studies have assessed child restraint practice in China. We aim to describe the prevalence of child restraint use and investigate risk factors affecting child restraint practice in Shanghai, China.Design and settingA cross-sectional observational study was conducted near children’s hospitals, kindergartens, entertainment places and shopping malls in Shanghai, China.ParticipantsEight rounds of data were collected between October 2015 and April 2019 with a total sample size of 12 061 children.Primary outcome measuresAt each site, trained field workers observed and recorded child restraint use in all passing motor vehicles with at least one child passenger.ResultsThe overall child safety restraint use rate was 6.42%. Child restraint use rate rose over time, from 5.12% in round 1% to 8.55% in round 8 (p<0.001). Results from the adjusted logistic regression model showed that children occupants with the following risk factors had a higher likelihood of child restraint use: children younger than 5 years compared with those aged 5–12 years (OR 2.12; 95% CI 1.78 to 2.53; p<0.001), sitting in rear seat compared with those in front seat (OR 31.80; 95% CI 4.45 to 227.14; p=0.001), children occupants observed near entertainment places (OR 2.34; 95% CI 1.67 to 3.28; p<0.001) or near shopping malls (OR 1.86; 95% CI 1.36 to 2.55; p<0.001) compared with those near children’s hospitals and transportation in the morning compared with afternoon (OR 1.30; 95% CI 1.04 to 1.62; p=0.021).ConclusionsThe overall child safety restraint use rate was low in Shanghai. Our findings may shed light on monitoring child restraint practice and have implications for intervention programmes for children occupants with the identified risk factors, which may help to promote child restraint use in motor vehicles and prevent road traffic injuries or deaths.

Rearward-Facing Infant Child Restraint Systems with Support Legs in Frontal and Frontal-Oblique Impacts

Previous studies of support legs in rearward-facing infant CRS models have focused on frontal impacts and have found that the presence of a support leg is associated with a reduction in head injury metrics. However, real-world crashes often involve an oblique principal direction of force. The current study used sled tests to evaluate the effectiveness of support legs in rearward-facing infant CRS models for frontal and frontal-oblique impacts with and without a simulated front row seatback. Frontal and frontal-oblique impact sled tests were conducted using the simulated Consumer Reports test method with and without the blocker plate, which was developed to represent a front row seatback. The Q1.5 anthropomorphic test device (ATD) was seated in rearward-facing infant CRS models, which were tested with and without support legs. The presence of a support leg was associated with significant reductions of head injury metrics below injury tolerance limits for all tests, which supports the findings of previous studies. The presence of a support leg was also associated with significant reductions of peak neck tensile force. The presence of the blocker plate resulted in greater head injury metrics compared to tests without the blocker plate, but the result was non-significant. However, the fidelity of the interaction between the CRS and blocker plate as an adequate representation of the interaction that would occur in a real vehicle is not well understood. The findings from the current study continue to support the benefit of support legs in managing the energy of impact for a child in a rearward-facing CRS.

Examining Diffusion and Convergence Processes of Three Road Safety Policies, 1964-2015

Global convergence of public policies has been regarded as a defining feature of the late twentieth century. This study explores the generalizability of this thesis for three road safety measures: i) road safety agencies; ii) child restraint laws; and iii) mandatory use of daytime running lights. We analyze cross-national longitudinal data using survival analysis for the years 1964-2015 in 181 countries. Our first main finding is that only child restraint laws have globally converged; in contrast, the other two policies exhibit a fractured global convergence process, likely as the result of competing international and national forces. This finding may reflect the lack of necessary conditions, at the regional and national levels, required to accelerate the spread of policies globally, adding further nuance to the global convergence thesis. A second finding is that mechanisms of policy adoption, such as imitation/learning and competition, rather than coercion, explain more consistently global and regional convergence outcomes in the road safety realm. This finding reinforces the idea of specific elective affinities, when explaining why the diffusion of policies may or not result in convergence. Lastly, by recognizing fractured convergence processes, our results call for revisiting the global convergence thesis and reintegrating more consistently regional analyses into policy diffusion and convergence studies.

Analysis of Injury Potential of Three-year-old Child Occupants Caused by Inappropriate Installation of Enhanced Child Restraint System with Top Tether in Frontal Crash Accidents

Objective: Frontal crash accidents remain a significant factor in causing the preventable injury and fatality for child occupants aged 3 in China. Despite the increased public awareness and utilization of child restraint system (CRS), inappropriate installations still exist and lead to a potential to result in injuries of head, thorax and abdomen regions of child occupants, especially when it comes to enhanced child restraint system (ECRS) with top tether. The current study focuses on the influence of top tether upon safety performance of ECRS with top tether in dynamic tests with different set-ups and explores the relationship between inappropriate installation of ECRS with top tether and the injury potential of child occupants aged 3 in a frontal crash. Methods: A testing scheme including 4 dynamic tests was devised to ascertain the extent to which the top tether affected the accelerations of thorax, the abdominal penetration and the head displacements. Different kinds of acceleration curves were employed to conduct the tests and to simulate the real status and situation of child occupants aged 3 in the CRS installed with top tether and without top tether respectively. Parameters of accelerations, abdominal penetrations, and head displacements were measured to analyze quantitatively the influence of inappropriate installations of ECRS with top tether under different conditions. Results: The safety performance of ECRS with the use of top tether was found better than that of ECRS without the use of top tether either in the normal condition or in the extreme condition. The test using the acceleration curves defined by regulations, the accelerations of thorax, abdominal penetrations, and head displacements of P3 manikin in the ECRS with the top tether connected to the anchor point revealed results that all met the requirements. While in the test using acceleration curves of the same kind, and when the top tether was not connected, the parameters measured displayed that the safety performance of the sample was worse than the former one. As for the tests using the more severe acceleration curves defined at will, it was more obvious that top tether could affect the function and safety performance of ECRS greatly, and the functional failure and severe damages occurred to the ECRS without the use of top tether. ECRS with the use of top tether was partly qualified even under the more severe conditions. Conclusions: Inappropriate installation of ECRS such as omitting the step of connecting top tether to anchor point could cause severe injuries and fatalities in frontal crash accidents. Effective measures should be taken to minimize the chances of inappropriate installations of ECRS.