This study examined the test-retest reliability of hallux flexion displacement measured using a smart sock system with embedded fiber Bragg grating (FBG) sensors. Thirty female participants consisting of 15 hallux valgus (HV) patients and 15 control participants were recruited. Maximum active hallux flexion displacement was measured twice on each participant in the first visit; the same procedures were repeated 7 days later. Intraclass correlation coefficients (ICC2,1) and standard error of measurement (SEM) were applied to test within-day and between-day reliability. Paired-samples T-test was performed to compare the displacements between trials. Results showed almost perfect within-day reliability for both HV and control groups (ICC=0.984 and 0.977, respectively) with small SEM (both 0.5cm). However, fair to moderate between-day reliability was found (0.323 and 0.438, respectively). Significant differences were found between repeated measurements taken on the same day (mean difference=0.3cm, p=0.023) and on different days (mean difference=1.6cm, p=0.027), though the effect size was small. The poorer between-day reliability is likely due to the inconsistency in fitting the sock onto the foot. Future optimization of the prototype design is called for to improve the fitting consistency of wearable sensors onto patients.

中文翻译：

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用于测量拇趾主动脚趾屈曲位移的基于 FBG 的智能袜子系统的日内和日间可靠性

本研究检查了使用带有嵌入式光纤布拉格光栅 (FBG) 传感器的智能袜子系统测量的拇趾屈曲位移的重测可靠性。招募了 30 名女性参与者，其中包括 15 名拇外翻 (HV) 患者和 15 名对照参与者。在第一次访问中，每个参与者测量了两次最大主动拇趾屈曲位移；7天后重复相同的程序。应用组内相关系数 (ICC2,1) 和测量标准误差 (SEM) 来测试日内和日间可靠性。进行配对样本 T 检验以比较试验之间的位移。结果显示，HV 组和对照组的日内可靠性几乎完美（国际商会=0.984和 0.977，分别）与小 SEM（均为 0.5厘米）。然而，发现了公平到中等的日间信度（分别为 0.323 和 0.438）。在同一天进行的重复测量之间发现了显着差异（平均区别=0.3厘米，p=0.023）和不同的日子（平均区别=1.6厘米，p=0.027)，尽管效果很小。较差的日间可靠性可能是由于将袜子安装到脚上的不一致。未来需要对原型设计进行优化，以提高可穿戴传感器在患者身上的贴合一致性。