Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2013 Sep;38(4):1021-5.
doi: 10.1016/j.gaitpost.2013.05.013. Epub 2013 Jun 21.

Falls Classification Using Tri-Axial Accelerometers During the Five-Times-Sit-To-Stand Test

Affiliations

Falls Classification Using Tri-Axial Accelerometers During the Five-Times-Sit-To-Stand Test

Emer P Doheny et al. Gait Posture. .

Abstract

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.

Keywords: Accelerometer; Classifier; Falls risk assessment; Logistic regression; Postural transitions.

Similar articles

See all similar articles

Cited by 13 articles

See all "Cited by" articles

Publication types

LinkOut - more resources

Feedback