Article

The five-times-sit-to-stand test (FTSS) is an established assessment of lower
limb strength, balance dysfunction and falls risk. Clinically, the time taken to
complete the task is recorded with longer times indicating increased falls risk.
Quantifying the movement using tri-axial accelerometers may provide a more
objective and potentially more accurate falls risk estimate. 39 older adults, 19
with a history of falls, performed four repetitions of the FTSS in their homes. A
tri-axial accelerometer was attached to the lateral thigh and used to identify
each sit-stand-sit phase and sit-stand and stand-sit transitions. A second
tri-axial accelerometer, attached to the sternum, captured torso acceleration.
The mean and variation of the root-mean-squared amplitude, jerk and spectral edge
frequency of the acceleration during each section of the assessment were
examined. The test-retest reliability of each feature was examined using
intra-class correlation analysis, ICC(2,k). A model was developed to classify
participants according to falls status. Only features with ICC>0.7 were
considered during feature selection. Sequential forward feature selection within
leave-one-out cross-validation resulted in a model including four reliable
accelerometer-derived features, providing 74.4% classification accuracy, 80.0%
specificity and 68.7% sensitivity. An alternative model using FTSS time alone
resulted in significantly reduced classification performance. Results suggest
that the described methodology could provide a robust and accurate falls risk
assessment.
CI - Copyright (c) 2013 Elsevier B.V. All rights reserved.

Langue : ANGLAIS