Citation

Urbanek JK, Harezlak J, Glynn NW, Harris T, Crainiceanu C, Zipunnikov V. Gait Posture 2016; 52: 217-223.

Affiliation

Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, MD 21205, United States.

Copyright

(Copyright © 2016, Elsevier Publishing)

DOI

10.1016/j.gaitpost.2016.11.045

PMID

27936440

Abstract

Many epidemiological and clinical studies use accelerometry to objectively measure physical activity using the activity counts, vector magnitude, or number of steps. These measures use just a fraction of the information in the raw accelerometry data as they are typically summarized at the minute level. To address this problem, we define and estimate two measures of temporal stride-to-stride gait variability based on raw accelerometry data: Amplitude Deviation (AD) and Phase Deviation (PD). We explore the sensitivity of our approach to on-body placement of the accelerometer by comparing hip, left and right wrist placements. We illustrate the approach by estimating AD and PD in 46 elderly participants in the Developmental Epidemiologic Cohort Study (DECOS) who worn accelerometers during a 400m walk test. We also show that AD and PD have a statistically significant association with the gait speed and sit-to-stand test performance.

Copyright © 2016 Elsevier B.V. All rights reserved.

Language: en