FUNCTIONAL MOBILITY CHARACTERIZES FALL STATUS
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time fallers and nonfallers on the Get Up and Go test and
differed only from one-time fallers on the Tandem Gait test.
Because one-time fallers were similar to frequent fallers on
all other measures, these two groups were collapsed for dis-
criminant function analyses. Our second research question
was to determine whether laboratory measures or mobility
measures best discriminated between the two new groups
contribute to a medically unstable profile, such as changes
in functional level, chronic disease, and medication use.
That the one-time fallers in our study performed similarly to
the frequent fallers on the Get Up and Go and that both
groups were significantly slower than nonfallers may indi-
cate subtle changes in lower extremity strength, power, and
mobility that simple tests measuring a single variable are
unable to pick up.
(fallers and nonfallers). We found that the Get Up and Go, a
test involving both lower extremity strength and power, and
mobility, was the best predictor of whether an individual
was a faller or a nonfaller.
Poor performance on the Tandem Gait test has been asso-
ciated with increased falls risk (7). The results of our study
support this finding. Nonfallers performed better than one-
time fallers on the Tandem Gait (p ϭ .005). Nonfallers were
faster than frequent fallers by an average of 3 seconds and
faster than the one-time fallers by over 4 seconds. These re-
sults were surprising. However, the frequent fallers required
more attempts to achieve two error-free trials as compared
with the nonfallers and required more assistance through
encouragement and coaching in order to achieve the re-
quired number of trials. This likely explains the slightly bet-
ter scores compared with one-time fallers and the fact that
scores did not quite reach statistical significance compared
with nonfallers. Chu and colleagues (7) found poor tandem
gait performance to be the most significant predictor of falls
followed by lower limb weakness in older hospital inpa-
tients. Others have found poor tandem gait ability in com-
munity-dwelling elderly individuals to be associated with
decreases in strength and balance (21,22). Thus, the Tan-
dem Gait test seems a reasonable tool for identifying fallers,
not only in frail hospital-bound elderly persons, but also in
healthy, independent-living elderly individuals.
We found that one-time and frequent fallers were more
similar across physical performance variables than were one-
time fallers and nonfallers. This is contrary to previous re-
ports (4,23). Focusing on falls rather than fallers, Nevitt and
colleagues (4) found that one-time falls are less predictable
than frequent falls, more likely to be associated with acci-
dents and overwhelming incidents than frequent falls, and
are therefore less indicative of those with a physiological
predisposition to falling. However, 37% of their study popu-
lation was between 60 and 69 years of age, and it is possible
that many of the one-time fallers were younger, particularly
given that age was reported as a risk factor for frequent falls.
Under our definition of a fall, and with close review of the
circumstances and characteristics of falls reported within our
study population, we found that the characteristics of one-
time falls were similar to the characteristics of frequent falls.
In addition, one-time fallers were similar to frequent fallers
with respect to both lower extremity strength and power and
to measures of functional mobility.
Our study has several strengths. First, three distinct
groups were evaluated. Other studies have examined differ-
ences in measures of strength and mobility in fallers and
nonfallers (7,17,18), but few have conducted a three-group
analysis consisting of nonfallers, one-time fallers, and fre-
quent fallers. Second, our elderly population was homoge-
nous with respect to age. Few studies have examined differ-
ences in physical performance measures between fallers and
nonfallers without attributing at least some of the differ-
ences to age. In addition, both men and women were in-
cluded in our study. Therefore, we are in a better position to
generalize our findings to elderly fallers of both genders.
Although falling is a significant problem for elderly women,
men are also at risk (19).
Our study also has several limitations. As with any case-
control study, there is a potential for unmeasured differ-
ences between cases and controls. However, the majority of
our population was recruited from a falls surveillance data-
base, all were independently dwelling, and none required
caregivers. Furthermore, medication use was similar across
groups. A second limitation is sample size. Statistical power
is lower for the measures of lower extremity strength and
power compared with the measures of gait. This may indi-
cate a smaller effect size related to strength and power. It is
also possible that the low reliability of the knee extension
and hip abduction measures influenced variability, which
likely affected statistical power. In addition, we were unable
to use ankle data on eight subjects, all of whom were non-
fallers.
We found that nonfallers performed better than both one-
time fallers and frequent fallers on the Get Up and Go, a
measure that was associated with both mobility and lower
extremity power (r ϭ Ϫ.32 to r ϭ .42, p Ͻ .001). Further-
more, the Get Up and Go was the best variable for cate-
gorizing individuals based on falls status, with 72% of all
subjects being correctly classified. These findings are con-
sistent with previous research. There is only one other re-
port using the Get Up and Go to discriminate fallers from
nonfallers. In a study of community-dwelling women over
To our surprise, lower extremity strength and power did
not discriminate between fallers and nonfallers. Our find-
ings for strength are consistent with those of Wooley and col-
leagues (18), who also utilized isometric measures and found
no differences in strength between elderly fallers and non-
fallers. However, they did not report reliability on their strength
measures. In an attempt to incorporate measures easily uti-
lized in a field setting, we chose an isometric dynamometer
for the measurement of lower extremity strength. Our data
show this to be unreliable for assessing lower extremity
strength in an elderly population and, as such, may account
6
5 years of age, O’Brian and colleagues (20) reported that
the Get Up and Go accurately categorized nonfallers 100%
of the time, although it was less sensitive in identifying fall-
ers (62%). However, they had only 13 fallers in their study.
In our study, by contrast, the Get Up and Go accurately
classified 98% of the fallers but was less sensitive in identi-
fying nonfallers. Previous work indicates that medically sta-
ble individuals vary little in their score on the Get Up and
Go over time (15). Thus, a poor performance on the Get Up
and Go could reflect subtle changes to falls risk factors that