Accident Research Centre, Monash University , Clayton , Australia.
Children's Hospital of Philadelphia , Philadelphia , Pennsylvania.
Traffic Inj Prev. 2019;20(7):713-719. doi: 10.1080/15389588.2019.1654093. Epub 2019 Sep 6.
Child occupant behavior and head position when travelling in child restraint systems (CRS) may have an effect on injury risk in the event of a motor vehicle crash. The current study aimed to describe the common characteristics and behaviors of child occupants during everyday, real-world motor vehicle travel in a sample of Australian families to identify potential safety implications of observed behaviors and head position within the CRS. Two instrumented study vehicles were used by 42 families for approximately two weeks. Continuous video and audio data were collected across 1,651 trips (over 600 hours). An online survey provided additional parent, familial and child occupant data. The characteristics and behaviors of 72 child occupants (aged 14 months to 9 years) who travelled in a forward-facing CRS (FFCRS) or a belt-positioning booster seat (BS) were observed and recorded by manual review of a sample of the video/audio recordings. One quarter of all trips ( = 414) was randomly selected for coding/analysis and, within each trip, one child occupant was selected who was travelling in a FFCRS or BS. Child occupant behaviors, head position within the FFCRS or BS, and other relevant information was coded for each trip during nine discrete five second intervals or 'epochs' (5%, 17%, 25%, 30%, 50%, 53%, 75%, 89% and 95% of trip duration). In the majority of epochs (74%), child occupants' heads were observed to be 'optimally' positioned within the FFCRS or BS. For more than half of the epochs, child occupants were observed to be: correctly restrained (58%) and involved in an interaction with another vehicle occupant (59%). Bivariate analyses revealed that children travelling in a FFCRS were significantly more likely to be observed to have optimal head positions than those travelling in a BS (78% vs. 62%), χ (1) = 86.00, < 0.001. Child occupants who were observed to be 'correctly' restrained were significantly more likely to be observed to have optimal head positions than those who were observed to be 'incorrectly' restrained (80% vs. 20%), χ (1) = 10.33, < 0.01. This is the first naturalistic driving study (NDS) to specifically explore the factors associated with child occupants' head position when travelling in a CRS. Findings from the current study can be used to inform the positioning of anthropometric test dummies (ATD) in CRS testing, guide improvements to CRS/vehicle design, and develop targeted educational strategies to improve child occupant safety.
儿童在汽车儿童约束系统（CRS）中的行为和头部位置可能会影响到发生车辆碰撞时的受伤风险。本研究旨在描述澳大利亚家庭中日常现实世界的汽车旅行中儿童乘客的常见特征和行为，以确定在 CRS 中观察到的行为和头部位置的潜在安全影响。 两个装有仪器的研究车辆被 42 个家庭使用了大约两周。在 1651 次旅行（超过 600 小时）中收集了连续的视频和音频数据。在线调查提供了额外的父母、家庭和儿童乘客数据。通过对视频/音频记录的样本进行手动审查，观察和记录了 72 名年龄在 14 个月至 9 岁之间的儿童乘客在正向安装的儿童约束系统（FFCRS）或安全带定位增高座椅（BS）中的特征和行为。所有旅行的四分之一（= 414）被随机选择进行编码/分析，并且在每次旅行中，选择一名正在 FFCRS 或 BS 中旅行的儿童乘客。在九个离散的五秒间隔（5%、17%、25%、30%、50%、53%、75%、89%和 95%的旅行持续时间）内，为每次旅行的每个儿童乘客的行为、FFCRS 或 BS 内的头部位置以及其他相关信息进行了编码/分析。在大多数间隔（74%）中，观察到儿童乘客的头部被“最佳”定位在 FFCRS 或 BS 内。在超过一半的间隔中，观察到儿童乘客：正确约束（58%）并与另一车辆乘客进行互动（59%）。双变量分析表明，与在 BS 中旅行的儿童相比，在 FFCRS 中旅行的儿童观察到的最佳头部位置的可能性明显更高（78%对 62%）， χ (1) = 86.00， < 0.001。与观察到的“不正确”约束的儿童相比，观察到的“正确”约束的儿童更有可能被观察到具有最佳头部位置（80%对 20%）， χ (1) = 10.33， < 0.01。这是第一项专门研究儿童在 CRS 中旅行时头部位置相关因素的自然驾驶研究（NDS）。本研究的结果可用于为 CRS 测试中的人体模型（ATD）定位提供信息，指导 CRS/车辆设计的改进，并制定有针对性的教育策略，以提高儿童乘客的安全性。
