Article

Gait variability is an important indicator of impaired mobility in
older adults; however, little is known about the meaning of change in gait
variability over time. This study estimated clinically meaningful change in
measures of gait variability using both distribution- and anchor-based
approaches. DESIGN: Community-based observational cohort study. SETTING: Bronx
County and the research center at Albert Einstein College of Medicine.
PARTICIPANTS: Of 1148 participants in the Einstein Aging Study, 241 had
quantitative gait assessments in two consecutive years between 2001 and 2005.
MEASUREMENTS: Gait variables were collected using a 12-foot instrumented walkway
as participants walked at their normal walking speed. Gait variability was
defined as the within-person standard deviation (SD) across steps in two 12-foot
walks. Distribution-based meaningful change estimates used Cohen's effect size
(0.2 for small and 0.5 for moderate effects). Anchor-based estimates were
obtained using dichotomous and ordinal self-reported walking ability ratings as
anchors. RESULTS: Distribution-based estimates for small and substantial changes
of variability measures were: stance time 0.005 and 0.014 s; swing time 0.003 and
0.009 s; step length 0.24 and 0.61 cm; and step width 0.03 and 0.08 cm. Among
those reporting no change in walking ability, measures of gait variability were
stable over 1 year. Among those reporting a decline in walking, stance time and
swing time variability increased. Among those reporting an improvement in
walking, only step length variability improved. CONCLUSION: Preliminary criteria
for meaningful change are 0.01 s for stance time and swing time variability and
0.25 cm for step length variability. These estimates may identify important
changes over time in both clinical settings and research studies.
CI - Copyright 2009 Elsevier B.V. All rights reserved.

Langue : ANGLAIS