Monaghan Kenneth, Delahunt Eamonn, Caulfield Brian
School of Physiotherapy and Performance Science, Motion Analysis Laboratory, University College Dublin, Ireland.
Gait Posture. 2007 Feb;25(2):303-15. doi: 10.1016/j.gaitpost.2006.04.011. Epub 2006 May 24.
This study investigates the optimum number of gait trial recordings to maximise intra-rater reliability with the CODA motion analysis system in a normal population. Potential sources of variability in test-retest experimental procedures will be discussed.
The most recent study by [Maynard V, Bakheit AMO, Oldham J, Freeman J. Intra-rater and inter-rater reliability of gait measurements with CODA mpx30 motion analysis system. Gait Posture 2003;17:59-67] that evaluated the Cartesian Optoelectronic Dynamic Anthropometer (CODA) motion analysis system exhibited poor correlation for intra-rater reliability of kinematic and kinetic parameters. It is unknown what the optimum number of gait trials is required during testing to represent an individuals gait pattern during normal walking.
Ten healthy subjects (mean 28.5 years) were tested on two occasions by an experienced well trained rater during normal walking to establish intra-rater reliability using 1-2, 1-4, 1-6, 1-8, and 1-10 gait trial recordings to represent the mean. The 3D kinematic, kinetic parameters of hip, knee and ankle joints and spatio-temporal parameters were recorded during normal walking. Intra-class correlation coefficient and Bland and Altman limits of agreement were chosen to analyse the results.
Spatio-temporal parameters exhibited least test-retest variability, as measurement of only two gait trials to represent the mean produced similar variability in test-retest as when higher numbers of trials were measured. Kinematic parameters were more variable than kinetic while for both variability decreased with increasing numbers of trials measured and would advocate measuring 10 gait trials for future analysis when measuring these parameters.
Generally intra-rater reliability improves when larger number of gait trial recordings represent a subject's gait.
本研究调查在正常人群中使用CODA运动分析系统时，为使评分者内信度最大化所需的步态试验记录的最佳数量。将讨论重测实验程序中潜在的变异性来源。
[Maynard V、Bakheit AMO、Oldham J、Freeman J。使用CODA mpx30运动分析系统进行步态测量的评分者内和评分者间信度。步态与姿势2003；17：59 - 67]的最新研究评估了笛卡尔光电动态人体测量仪（CODA）运动分析系统，结果显示运动学和动力学参数的评分者内信度相关性较差。在测试过程中，尚不清楚需要进行多少次步态试验才能代表个体正常行走时的步态模式。
10名健康受试者（平均年龄28.5岁）在正常行走时由一名经验丰富且训练有素的评分者进行了两次测试，以使用1 - 2、1 - 4、1 - 6、1 - 8和1 - 10次步态试验记录来确定评分者内信度，取平均值。在正常行走过程中记录了髋、膝和踝关节的三维运动学、动力学参数以及时空参数。选择组内相关系数和Bland - Altman一致性界限来分析结果。
时空参数的重测变异性最小，因为仅测量两次步态试验来取平均值所产生的重测变异性与测量更多次数试验时相似。运动学参数比动力学参数更具变异性，并且对于两者而言，随着测量的试验次数增加，变异性均降低，因此在测量这些参数时，建议未来分析测量10次步态试验。
一般来说，当用更多数量的步态试验记录来代表受试者的步态时，评分者内信度会提高。
