Simple Measurement of Temporal and Spatial Gait Variables Using a Video Browser: Concurrent Validity and Intra-rater and Inter-rater Reliability

[Purpose] Using a video browser (VB), we measured the step time and step length during gait, and investigated the concurrent validity, and intra- and inter-rater reliabilities. [Subjects] The subjects were 10 normally healthy women, and the assessors were a physical therapist and a physical therapy student. [Method] The walking conditions were normal walking and walking with an orthosis, and we recorded walking at a comfortable speed over a 10-m course. We assessed the reliability and validity of the step time and step length measured using VB, and spatial coordinates (3D) derived from the video data. [Results] Under each walking condition, there were significant regression coefficients for 3D and VB, the intra-class correlation coefficients ranged from 0.78 ~ 1.00, and the error value was small. [Conclusion] The measurement of step time and step length using VB is simple, objective and economical, making it useful in the clinical setting for the gait analysis of cases showing gait disorders.