Validation of centre of pressure trajectory measurement from a pressure tile system during standing and locomotor tasks

Abstract

This study validated a portable pressure tile system (StepScan™) by comparing its centre of pressure (CoP) measurements to those from in-floor AMTI™ force plates during a dynamic Step-Up Step-Down (SUSD) task. Thirty healthy adults completed the task while data were collected simultaneously from both systems. Intraclass Correlation Coefficient analysis showed strong agreement across CoP metrics (r > 0.88, p < 0.001), with Bland-Altman plots indicating moderate agreement and no systematic bias. A secondary aim explored age-related differences in spatiotemporal parameters. Older adults exhibited significantly higher step width variability (p < 0.05), particularly in the mediolateral direction, suggesting reduced stability. A weak but positive correlation (r= 0.44, R² = 0.191) was observed between age and postural sway. Finally, time-varying CoP data from StepScan™ demonstrated reliable error estimates, supporting its use in clinical balance assessments outside lab settings. This is the first study to validate StepScan™ against a gold-standard force plate during a functional mobility task.