Calibrating and validating accelerometry for use across early childhood (6-24 months)

项目摘要 加速度计是客观测量身体活动的标准，但令人惊讶的是， 在2岁之前的幼儿期使用加速度计的最佳做法。基于hip 加速度测量法对于婴儿和幼儿可能是不舒服的，特别是在睡眠期间， 合规性和限制性综合24小时测量。在脚踝处佩戴该装置可以克服 这些限制，但数据的性能脚踝为基础的加速度来分类身体活动 幼儿期的强度是稀疏的。一项研究支持踝关节加速度计的有效性， 尽管这种方法还没有被一个独立的研究小组复制。 此外，通过加速度计校准移动的但尚未走动的 婴儿缺乏。我们的长期目标是开发针对体育活动的肥胖预防干预措施 在我们农村社区的家庭中，该项目的目标是评估 踝关节加速度测量法在测量6-24个月大婴儿身体活动中的有效性，这是一个关键阶段， 支持发展身体活动行为。我们的基本原理是提供一种有效的方法来衡量儿童的 24-在多天评估中使用一个设备进行数小时的运动和睡眠，对父母的负担最小 和儿童我们的具体目标是1）校准和验证算法，以分类体力活动强度 用于行走前和行走的婴儿和幼儿（6-24个月），使用踝关节和髋关节 加速度计，并比较两个磨损部位之间的性能，和2）评估的可行性 踝关节与髋关节加速度计的穿戴协议和体力活动强度分类， 6-24个月大的婴儿在自然环境中进行为期多日的评估。两个目标都将使用ActiGraph GT 3X+加速度计。在第一个目标中，将鼓励儿童参与一系列半结构化的 不同强度的活动，同时佩戴两个加速度计，一个在脚踝，一个在臀部。我们将 根据直接观察校准两种设备，并评估每种设备的相对性能。在目标2中， 另一个6-24个月大的婴儿样本将被要求在脚踝和臀部连续佩戴加速度计 在自然环境下，我们将比较父母的满意度， 方案，以及两个磨损部位的每日体力活动强度估计值。这项拟议的研究是 创新，在我们看来，因为它侧重于脚踝为基础的加速度测量的可能性， 在幼儿阶段的体力活动强度，并旨在分类体力活动强度使用 术前婴儿的加速度测量数据。这项研究具有重要意义，因为它将提供 为该年龄组提供最佳加速度测量方法所需的关键数据， 通过基于脚踝的加速度计测量24小时内的身体活动和睡眠。

Project Summary Accelerometry is standard for objectively measuring physical activity, yet there is surprisingly limited data for best practices when using accelerometry during early childhood, before the age of 2 years. Hip-based accelerometry may be uncomfortable for infants and toddlers particularly during periods of sleep, thus reducing compliance and limiting integrated 24-hour measurements. Wearing the device at the ankle may overcome such limitations, yet data on the performance of ankle-based accelerometry to classify physical activity intensity during early childhood is sparse. One study supports the validity of ankle-based accelerometry among toddlers as young as 14 months, yet the approach has yet to be replicated by an independent research group. Furthermore, data to calibrate physical activity intensity via accelerometry among mobile yet pre-ambulatory infants are lacking. Our long-term goal is to develop obesity-prevention interventions targeting physical activity and sleep during early childhood for families in our rural communities. The goal of this project is to assess the validity of ankle-based accelerometry in measuring physical activity among 6-24-month-olds, a critical stage to support developing physical activity behaviors. Our rationale is to provide a valid method to measure children’s 24-hour movement and sleep with one device over a multiple-day assessment with minimal burden on parents and children. Our specific aims are to 1) Calibrate and validate algorithms to classify physical activity intensity for pre-ambulatory and ambulatory infants and toddlers (6-24 months old) using ankle- and hip-based accelerometry and compare the performance between the two wear sites, and 2) Assess the feasibility of the wear protocol and classification of physical activity intensity for ankle- versus hip-based accelerometry among 6-24-month-olds during a multiple-day assessment in their natural settings. Both aims will use the ActiGraph GT3X+ accelerometer. In the first aim, children will be encouraged to engage in a series of semi-structured activities of varying intensities while wearing two accelerometers, one at the ankle and one at the hip. We will calibrate both devices against direct observation and assess the relative performance of each. In aim 2, another sample of 6-24-month-olds will be asked to wear an accelerometer at the ankle and hip continuously over four days in their natural settings, and we will compare parent satisfaction, compliance with the wear protocol, and estimates of daily physical activity intensity across the two wear sites. This proposed research is innovative, in our opinion, because it focuses on the possibility of ankle-based accelerometry to measure physical activity intensity during the early childhood stage and aims to classify physical activity intensity using accelerometry data for pre-ambulatory infants. This proposed research is significant because it will provide critical data needed to inform best practices for accelerometry for this age group and may facilitate integrated measurements of physical activity and sleep over 24-hours via ankle-based accelerometry.