TY  - JOUR
PY  - 2019//
TI  - Walking-speed estimation using a single inertial measurement unit for the older adults
JO  - PLoS one
A1  - Byun, Seonjeong
A1  - Lee, Hyang Jun
A1  - Han, Ji Won
A1  - Kim, Jun Sung
A1  - Choi, Euna
A1  - Kim, Ki Woong
SP  - e0227075
EP  - e0227075
VL  - 14
IS  - 12
N2  - BACKGROUND: Although walking speed is associated with important clinical outcomes and designated as the sixth vital sign of the elderly, few walking-speed estimation algorithms using an inertial measurement unit (IMU) have been derived and tested in the older adults, especially in the elderly with slow speed. We aimed to develop a walking-speed estimation algorithm for older adults based on an IMU. <br><br>METHODS: We used data from 659 of 785 elderly enrolled from the cohort study. We measured gait using an IMU attached on the lower back while participants walked around a 28 m long round walkway thrice at comfortable paces. Best-fit linear regression models were developed using selected demographic, anthropometric, and IMU features to estimate the walking speed. The accuracy of the algorithm was verified using mean absolute error (MAE) and root mean square error (RMSE) in an independent validation set. Additionally, we verified concurrent validity with GAITRite using intraclass correlation coefficients (ICCs). <br><br>RESULTS: The proposed algorithm incorporates the age, sex, foot length, vertical displacement, cadence, and step-time variability obtained from an IMU sensor. It exhibited high estimation accuracy for the walking speed of the elderly and remarkable concurrent validity compared to the GAITRite (MAE = 4.70%, RMSE = 6.81
LA  - en
SN  - 1932-6203
UR  - http://dx.doi.org/10.1371/journal.pone.0227075
ID  - ref1
ER  -