Geriatric Education and Research Institute Ltd, 2 Yishun Central 2, Singapore, 768024, Singapore.
NDR Medical Technology Pte Ltd, 75 Ayer Rajah Crescent #02-19, Singapore, 139953, Singapore.
BMC Geriatr. 2020 Jul 22;20(1):251. doi: 10.1186/s12877-020-01649-x.
There is increasing interest in examining the life space mobility and activity participation of older adults in the community using sensor technology. Objective data from these technologies may overcome the limitations of self-reported surveys especially in older adults with age-associated cognitive impairment. This paper describes the development and validation of a prototype hybrid mobility tracker for assessing life space mobility and out-of-home activities amongst 33 community-ambulant older adults in Singapore.
A hybrid mobility tracker was developed by combining a passive Global Positioning System logger, tri-axial accelerometer and radio-frequency identification. Objective measures of life space, derived from 1 week of tracking data using Geographic Information Systems, were the maximum Euclidean distance from home (Max Euclid) and the area of the minimum convex polygon surrounding all GPS waypoints (MCP area). Out-of-home activities were quantified by visually identifying the total number of activity nodes, or places where participants spent ≥5 min, from mobility tracks. Self-reported measure of life space in 4 weeks was obtained using the University of Alabama at Birmingham Study of Life Space Assessment (UAB-LSA) questionnaire. Self-reported out-of-home activities were recorded daily in a travel diary for 1 week. Bivariate correlations were used to examine convergent validity between objective and subjective measures of life space and out-of-home activities.
The mean age of participants was 69.2 ± 7.1 years. The mean UAB-LSA total score was 79.1 ± 17.4. The median (range) Max Euclid was 2.44 km (0.26-7.50) per day, and the median (range) MCP area was 3.31 km (0.03-34.23) per day. The UAB-LSA total score had good correlation with Max Euclid (r = 0.51, p = 0.002), and moderate correlation with MCP area (r = 0.46, p = 0.007). The median (range) total number of activity nodes measured by tracker of 20 (8-47) per week had a good correlation with the total activity count recorded in the travel diaries of 15 (6-40) per week (r = 0.52, p = 0.002).
The tracking system developed to understand out-of-home travel was feasible and reliable. Comparisons with the UAB-LSA and travel diaries showed that it provided reliable and valid spatiotemporal data to assess the life space mobility and activity participation of older adults.
使用传感器技术越来越多地关注社区中老年人的生活空间移动性和活动参与度。这些技术的客观数据可能克服自我报告调查的局限性，尤其是在伴有与年龄相关的认知障碍的老年人中。本文描述了一种用于评估新加坡 33 名社区活动老年人生活空间移动性和户外活动的混合移动追踪器原型的开发和验证。
通过将被动全球定位系统记录器、三轴加速度计和射频识别器组合，开发了一种混合移动追踪器。使用地理信息系统从 1 周的跟踪数据中得出的生活空间的客观指标包括离家的最大欧几里得距离（Max Euclid）和围绕所有 GPS 航点的最小凸多边形的面积（MCP 面积）。通过从移动轨迹中视觉识别参与者花费≥5 分钟的总活动节点数（或活动地点数）来量化户外活动。使用伯明翰阿拉巴马大学生活空间评估研究（UAB-LSA）问卷在 4 周内获得生活空间的自我报告测量值。在一周内每天在旅行日记中记录日常户外活动。使用双变量相关性来检查生活空间和户外活动的客观和主观测量之间的收敛有效性。
参与者的平均年龄为 69.2±7.1 岁。UAB-LSA 的平均总分是 79.1±17.4。Max Euclid 的中位数（范围）为每天 2.44 公里（0.26-7.50），MCP 面积的中位数（范围）为每天 3.31 公里（0.03-34.23）。UAB-LSA 总分与 Max Euclid 相关性良好（r=0.51，p=0.002），与 MCP 面积相关性适中（r=0.46，p=0.007）。通过追踪器测量的每周活动节点总数中位数（范围）为 20（8-47），与旅行日记中每周活动计数中位数（范围）为 15（6-40）相关性良好（r=0.52，p=0.002）。
为了解户外活动而开发的跟踪系统是可行且可靠的。与 UAB-LSA 和旅行日记的比较表明，它提供了可靠和有效的时空数据，可用于评估老年人的生活空间移动性和活动参与度。
