Aims: To examine concurrent and construct validity of inertial sensor 360°turn measures in relation with motion capture and mobility assessments in cognitively impaired older adults.
Methods: Data was collected in 31 participants, mean age 85.2 (SD 5.2), during clockwise (CW) and counter clockwise (CCW) 360° turns using (1) APDM body-worn inertial sensors and (2) Qualisys 8-camera laboratory-based motion capture.
Results: Absolute agreement between inertial sensor and motion capture measures was excellent for turn duration and turn peak velocity (ICC = 0.96-0.98). Strong to moderate correlations were present between inertial sensor turn measures and performance on the Timed Up and Go, Short Physical Performance Battery and 90-s Balance Test. ROC curve analysis of CCW 360° turn duration and turn peak velocity distinguished higher risk versus lower risk for mobility disability.
Conclusions: Inertial sensor 360° turn measures demonstrated concurrent and construct validity in relation to motion capture and mobility assessments.
Keywords: Inertial sensors; cognitive impairment; mobility disability; older adults; turns.