Article

The current 'gold standard' for clinical evaluation of freezing of gait (FOG) in
Parkinson's disease (PD) is determination of the number of FOG episodes from
video by independent raters. We have previously described a robust technique for
objective FOG assessment from lower-limb acceleration. However, there is no
existing method for validation of autonomous FOG measures in the absence of video
documentation. In this study we compared the results of clinical evaluation of
FOG from computer-generated animations (derived from body-mounted inertial
sensors) during a timed up and go test with the 'gold standard' of clinical video
assessment, utilizing a cohort of 10 experienced raters from four PD centers.
Agreement between the 10 clinical observers for scoring of FOG from computer
animations was more robust for the relative duration of freeze events (percent
time frozen; intraclass correlation coefficient of 0.65) than number of FOG
episodes, and was comparable with clinical evaluation of the patient from video
(intraclass correlation coefficient 0.73). This result suggests that percent time
frozen should be considered (along with number of FOG events) to better convey
FOG severity. The ability of clinical observers to quantify FOG from
computer-generated animation derived from lower-limb motion data provides a
potential approach to validation of accelerometry-based FOG identification
outside of the clinic.
CI - Copyright (c) 2013 Elsevier B.V. All rights reserved.

Langue : ANGLAIS