Concurrent Validity of a Commercial Wireless Trunk Triaxial Accelerometer System for Gait Analysis

Area of Science:

• Biomechanics
• Wearable Technology
• Gait Analysis

Background:

• Wearable sensors offer cost-effectiveness, ease of use, and real-time feedback for motion analysis.
• Wireless capabilities are crucial for full-body motion tracking, especially in dynamic environments like sports.
• Reliability and validity studies are essential for commercially available sensor systems.

Purpose of the Study:

• To assess the test-retest reliability of the BTS G-WALK® sensor system.
• To determine the concurrent validity of the BTS G-WALK® system against the GAITRite® walkway system.
• To evaluate the system's accuracy for various spatiotemporal gait parameters.

Main Methods:

• A reliability and concurrent validity study was conducted in a laboratory setting.
• Thirty healthy participants were recruited for the study.
• Spatiotemporal gait parameters including speed, cadence, stride length, and various support/swing durations were measured.

Main Results:

• The BTS G-WALK® system exhibited excellent test-retest reliability (ICC = .85–.99) for all measured parameters.
• Excellent concurrent validity (ICC = .88–.97) was found for speed, cadence, stride length, and stride duration.
• Poor to moderate validity (ICC = .12–.47) was observed for stance, swing, and single/double support durations, with wider limits of agreement for single/double support.

Conclusions:

• The BTS G-WALK® sensor system is reliable for measuring all spatiotemporal gait parameters.
• The system demonstrates excellent concurrent validity for key gait parameters like speed and stride length.
• Careful consideration is advised when interpreting temporal parameters related to foot contact, such as stance, swing, and support times.