Reliability and minimal detectible change values for gait kinematics and kinetics in healthy adults

Computerized assessment of gait is commonly used in both research and clinical settings to quantify gait mechanics and detect change in performance. Minimal Detectable Change values have only recently been reported, are only available for patient populations, and in many cases exceed 10°. Twenty nine healthy individuals underwent two biomechanical gait assessments separated by 5.6 (SD 2.2) days, with two raters for each session. All subjects walked at a self selected pace and three controlled velocities. ICC, SEM and MDC for kinematic and kinetic measures were calculated for interrater-intrasession, intrarater-intersession and interrater-intersession. ICC values were in the good to excellent range (r > 0.75) for all kinematic and kinetic variables and all comparisons. MDC values were lower than previously published data for all similar comparisons. The results of the current study suggest that reliability is good to excellent across a range of controlled walking velocities and the introduction of a second rater does not appreciably impact ICC or MDC values. In young healthy adults changes in gait kinematics of greater than approximately 5° can be identified when comparing between sessions.