Instrumenting gait with an accelerometer: a system and algorithm examination.

Area of Science:

• Biomechanics
• Wearable Technology
• Gerontology

Background:

• Gait analysis is crucial for assessing general health, but traditional laboratory methods are complex and restrictive.
• Body-worn sensors (BWM) offer a promising, accessible alternative for real-world gait measurement.
• Recent advancements enable BWM to capture spatio-temporal gait characteristics outside laboratory settings.

Purpose of the Study:

• To validate a low-cost body-worn sensor (BWM) against laboratory-based gait analysis in younger and older adults.
• To assess the BWM's accuracy in measuring total step count, mean spatio-temporal gait characteristics, variability, and asymmetry.
• To investigate discrepancies observed between the BWM and laboratory reference systems.

Main Methods:

• A robust testing protocol was employed comparing a low-cost BWM with a laboratory reference system.
• Participants included both younger and older adult cohorts.
• Detailed analysis was performed to identify the sources of disagreement between the two measurement systems.

Main Results:

• The BWM demonstrated validity in estimating total step count and mean spatio-temporal gait parameters.
• Agreement between the BWM and laboratory reference was poor for gait variability and asymmetry measures.
• Discrepancies were attributed to inherent differences between the measurement systems, not sensor limitations.

Conclusions:

• The validated BWM shows potential for collecting longitudinal, real-world gait data in large-scale studies.
• Further algorithm refinement is necessary to improve the accuracy of gait variability and asymmetry measurements.
• Caution is advised when selecting reference systems for validating wearable gait sensors.