An assessment of child passenger safety levels of service in Michigan

Objective: The purpose of this article was to assess the match between child passenger safety resources (child passenger safety technicians [CPSTs], car seat checks, and child restraint system [CRS] distribution programs) and the child population in Michigan by utilizing geographic information systems approaches and to analyze the impact of Michigan’s CPSTs on child passenger safety behaviors on departure from a seat check. Methods: Data were collected from administrative sources and a survey of CPSTs to determine the number and location of child passenger safety resources and children in Michigan. The main analyses used data from 2014. The child population ≤4 years old per county and per traffic safety region was determined from census data. CPST and car seat check locations were determined from a list from the Michigan Office of Highway Safety Planning (Mi-OHSP) and a survey of CPSTs who coordinate seat checks. Summary sheets from Mi-OHSP served as the data source for CRSs distributed through their occupant protection program. Data from child passenger safety checklists completed with seat checks were obtained from Safe Kids Michigan. Addresses were geocoded using Google Maps Geocoding API and then mapped at the county level using ArcGIS Desktop 10.3.1. Descriptive statistics were calculated and levels of service were determined at the county and regional levels. Results: In 2014, there were 570,929 children ≤4 years old in Michigan and 979 CPSTs who worked at 209 known seat check locations. An average of 6,854 seats was checked per year through Safe Kids Michigan Coalitions. All but 3 regions met an intermediate service level for seat check locations by offering one or more per 5,000 children ≤4 years old. There was at least one CPST in 80 of 83 counties (median 5; interquartile range, 2, 10.5). Assuming that an average Michigan CPST provides 10 h of service each year, all but 2 regions reached an intermediate service level of at least one technician hour per 90 children ≤4 years old. Fewer regions reached a basic level of service for the number of seat checks. Almost half (49.5%) of Safe Kids Michigan seat checks resulted in a change in child passenger safety behaviors. Conclusions: Child passenger safety resources in Michigan are not evenly distributed yet most regions and counties meet intermediate levels of service. Reallocating resources to areas that are providing basic levels of service could help reduce disparities in child passenger safety behaviors.

研究目的：本文旨在通过地理信息系统（Geographic Information Systems, GIS）方法，评估密歇根州儿童乘客安全资源（儿童乘客安全技术人员（Child Passenger Safety Technicians, CPSTs）、汽车安全座椅检查及儿童约束系统（Child Restraint System, CRS）分发项目）与当地儿童人口的匹配程度，并分析密歇根州CPSTs对参与者在座椅检查后儿童乘客安全行为的影响。
研究方法：本研究从行政数据源及CPSTs调查问卷中收集数据，以确定密歇根州儿童乘客安全资源的数量与位置，以及当地儿童人口规模。核心分析采用2014年的相关数据。通过人口普查数据获取各郡县及各交通安全区域内≤4岁儿童的人口数量。CPST及汽车安全座椅检查的点位信息来自密歇根州公路安全规划办公室（Mi-OHSP）提供的清单，以及协调座椅检查工作的CPSTs调查问卷结果。Mi-OHSP提供的汇总表作为其乘员保护项目下分发的CRS数量的数据来源。来自密歇根州安全儿童组织（Safe Kids Michigan）的座椅检查配套儿童乘客安全检查表数据亦被纳入分析。所有地址均通过谷歌地图地理编码API（Google Maps Geocoding API）完成地理编码，随后使用ArcGIS Desktop 10.3.1在郡县级别进行制图。本研究计算了描述性统计量，并确定了郡县及区域层面的服务水平。
研究结果：2014年，密歇根州≤4岁儿童总数为570929人，共有979名CPSTs在209个已知的座椅检查点位开展工作。密歇根州安全儿童联盟年均完成约6854次座椅检查。除3个区域外，其余所有区域均达到座椅检查点位的中级服务水平，即每5000名≤4岁儿童对应至少1个座椅检查点位。83个郡县中有80个至少配备1名CPST（中位数为5，四分位距为2~10.5）。假设密歇根州每名CPST年均提供10小时服务，则除2个区域外，其余所有区域均达到中级服务水平，即每90名≤4岁儿童对应至少1名技术人员服务时长。达到座椅检查数量基础服务水平的区域较少。近半数（49.5%）密歇根州安全儿童组织的座椅检查可促使参与者改变儿童乘客安全行为。
研究结论：密歇根州的儿童乘客安全资源分布并不均衡，但多数区域及郡县已达到中级服务水平。将资源重新分配至尚未达到基础服务水平的区域，有助于缩小儿童乘客安全行为方面的差距。