Menzies Research Institute, University of Tasmania, Hobart, Tasmania 7000, Australia.
Gait Posture. 2011 Jul;34(3):374-8. doi: 10.1016/j.gaitpost.2011.06.004. Epub 2011 Jul 7.
There are few empirical data to guide the choice of a gait initiation (GI) measure in older people. We investigated the statistical characteristics of the components of GI, their inter-relationships and associations with sensorimotor variables, and the effect on them of cognitive interference.
GI was measured for randomly selected participants aged 60-86 years using a force-platform with and without a cognitive interference task. Sensorimotor measures were obtained using the physiological profile assessment (PPA), and cognitive speed using the digit symbol and symbol search tests. GI was divided into its three components: time to first lateral movement (FLM); transfer time; and swing time. Six summary indices were assessed for suitability. Regression techniques and Spearman correlations were used to examine learning effects, inter-relationships between components, associations with other study factors and responsiveness to cognitive interference.
The median of trials per participant was the best summary index. Learning effects were observed under single and particularly dual-tasking. Time to FLM was most consistently associated with age, height, weight, sensorimotor variables, falls-risk score and cognitive speed, and was most responsive to dual-tasking. Overall time to GI was more predictive of falls risk than was time to FLM.
Multiple trials are recommended for GI component measurement and the median may provide the best summary measure across trials. Time to FLM is the GI component measure of choice in older people due to its relationship with other factors and responsiveness to cognitive interference but without advantage over overall time to GI.
指导老年人步态起始（GI）测量选择的经验数据很少。我们研究了 GI 成分的统计特征、它们之间的相互关系以及与感觉运动变量的关联，以及认知干扰对它们的影响。
使用带有和不带有认知干扰任务的力台，随机选择 60-86 岁的参与者测量 GI。使用生理概况评估（PPA）获得感觉运动测量值，使用数字符号和符号搜索测试获得认知速度。将 GI 分为三个组成部分：第一次侧向移动（FLM）的时间；转移时间；和摆动时间。评估了六个综合指标的适用性。使用回归技术和 Spearman 相关系数来检查学习效果、组件之间的相互关系、与其他研究因素的关联以及对认知干扰的反应能力。
参与者每次试验的中位数是最佳综合指标。在单任务和特别是双重任务下观察到学习效果。FLM 的时间与年龄、身高、体重、感觉运动变量、跌倒风险评分和认知速度最一致相关，并且对双重任务最敏感。整体 GI 时间比 FLM 时间更能预测跌倒风险。
建议对 GI 成分测量进行多次试验，中位数可能是试验中最佳的综合测量值。由于与其他因素的关系以及对认知干扰的敏感性，FLM 时间是老年人 GI 成分测量的首选，但不如整体 GI 时间有优势。
