Department of Internal Medicine and Geriatrics, Angers University Hospital (4 rue larrey), Angers (F-49933), France.
J Neuroeng Rehabil. 2011 Jul 11;8(1):37. doi: 10.1186/1743-0003-8-37.
Although test-retest reliability of mean values of spatio-temporal gait parameters has been assessed for reliability while walking alone (i.e., single tasking), little is known about the test-retest reliability of stride time variability (STV) while performing an attention demanding-task (i.e., dual tasking). The objective of this study was to examine immediate test-retest reliability of STV while single and dual tasking in cognitively healthy older individuals (CHI) and in demented patients with frontotemporal degeneration (FTD).
Based on a cross-sectional design, 69 community-dwelling CHI (mean age 75.5 ± 4.3; 43.5% women) and 14 demented patients with FTD (mean age 65.7 ± 9.8 years; 6.7% women) walked alone (without performing an additional task; i.e., single tasking) and while counting backward (CB) aloud starting from 50 (i.e., dual tasking). Each subject completed two trials for all the testing conditions. The mean value and the coefficient of variation (CoV) of stride time while walking alone and while CB at self-selected walking speed were measured using GAITRite® and SMTEC® footswitch systems.
ICC of mean value in CHI under both walking conditions were higher than ICC of demented patients with FTD and indicated perfect reliability (ICC > 0.80). Reliability of mean value was better while single tasking than dual tasking in CHI (ICC = 0.96 under single-task and ICC = 0.86 under dual-task), whereas it was the opposite in demented patients (ICC = 0.65 under single-task and ICC = 0.81 under dual-task). ICC of CoV was slight to poor whatever the group of participants and the walking condition (ICC < 0.20), except while dual tasking in demented patients where it was fair (ICC = 0.34).
The immediate test-retest reliability of the mean value of stride time in single and dual tasking was good in older CHI as well as in demented patients with FTD. In contrast, the variability of stride time was low in both groups of participants.
尽管已经评估了时空步态参数均值的重测信度在单独行走时（即单任务）的可靠性，但在执行注意力要求任务（即双任务）时步长时间变异（STV）的重测信度知之甚少。本研究的目的是检验认知健康老年人（CHI）和额颞叶变性（FTD）痴呆患者在单任务和双任务时 STV 的即时重测信度。
基于横断面设计，纳入 69 名社区居住的 CHI（平均年龄 75.5 ± 4.3 岁；43.5%为女性）和 14 名额颞叶变性（FTD）痴呆患者（平均年龄 65.7 ± 9.8 岁；6.7%为女性），在不进行额外任务（即单任务）的情况下单独行走（即单任务）和倒计数（CB）从 50 开始（即双任务）。每位受试者在所有测试条件下完成两次试验。使用 GAITRite®和 SMTEC®脚踏开关系统测量单独行走和 CB 时的步长时间的平均值和变异系数（CoV）。
在两种行走条件下，CHI 的平均值的 ICC 均高于额颞叶变性（FTD）痴呆患者，表明具有完美的可靠性（ICC > 0.80）。CHI 患者在单任务时的平均值的可靠性优于双任务（单任务时 ICC = 0.96，双任务时 ICC = 0.86），而在痴呆患者中则相反（单任务时 ICC = 0.65，双任务时 ICC = 0.81）。无论参与者群体和行走条件如何（ICC < 0.20），CoV 的 ICC 均为轻微至较差，除了痴呆患者在双任务时为适度（ICC = 0.34）。
在认知健康的老年人以及额颞叶变性（FTD）痴呆患者中，单任务和双任务时步长时间均值的即时重测信度均良好。相比之下，两组参与者的步长时间变异性均较低。
